ETH Price: $2,199.48 (-9.12%)

Transaction Decoder

Block:
21489256 at Dec-26-2024 09:14:35 PM +UTC
Transaction Fee:
0.001259869147045092 ETH $2.77
Gas Used:
147,802 Gas / 8.524033146 Gwei

Emitted Events:

144 TetherToken.Transfer( from=[Receiver] GnosisSafeProxy, to=0xDb9C8be99eB910FED90dF317f845bF0B722ec0a6, value=1400000000 )
145 ERC1967Proxy.0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef( 0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef, 0x000000000000000000000000c3dd26450475920642538ea6c360e8283e7eb04c, 0x0000000000000000000000006077807f90841db9150e35f42182a29e6d7e1963, 000000000000000000000000000000000000000000000000000000003b9aca00 )
146 GnosisSafeProxy.0x442e715f626346e8c54381002da614f62bee8d27386535b2521ec8540898556e( 0x442e715f626346e8c54381002da614f62bee8d27386535b2521ec8540898556e, 2de9b3628dd9f95501520d14152b22a9974406afa2f5f292a4450d98023ef8f1, 0000000000000000000000000000000000000000000000000000000000000000 )

Account State Difference:

  Address   Before After State Difference Code
(Titan Builder)
12.736525157293885436 Eth12.736634724249363872 Eth0.000109566955478436
0xa54e44f2...742D4C38e
0.014177743691779976 Eth
Nonce: 50
0.012917874544734884 Eth
Nonce: 51
0.001259869147045092
0xC3DD2645...83E7eb04C
0xd1d2Eb1B...262C87cae
0xdAC17F95...13D831ec7

Execution Trace

GnosisSafeProxy.6a761202( )
  • GnosisSafe.execTransaction( to=0x40A2aCCbd92BCA938b02010E17A5b8929b49130D, value=0, data=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operation=1, safeTxGas=0, baseGas=0, gasPrice=0, gasToken=0x0000000000000000000000000000000000000000, refundReceiver=0x0000000000000000000000000000000000000000, signatures=0x000000000000000000000000A54E44F29E3CBECD4898D3EBA4CA837742D4C38E0000000000000000000000000000000000000000000000000000000000000000014B4CD695802B206415BBC4B9972A7D4EFABB6B024A957B7C439300A122E79F92663714379F8A5E658C1DC23AA1AEE3F45B7BD5137AAE8CEF38953FFB6FC2F9781B ) => ( success=True )
    • Null: 0x000...001.2de9b362( )
    • MultiSendCallOnly.multiSend( transactions=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
      • TetherToken.transfer( _to=0xDb9C8be99eB910FED90dF317f845bF0B722ec0a6, _value=1400000000 )
      • ERC1967Proxy.a9059cbb( )
        • Gala.transfer( to=0x6077807f90841Db9150e35F42182A29e6D7E1963, amount=1000000000 ) => ( True )
          File 1 of 6: GnosisSafeProxy
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          
          /// @title IProxy - Helper interface to access masterCopy of the Proxy on-chain
          /// @author Richard Meissner - <[email protected]>
          interface IProxy {
              function masterCopy() external view returns (address);
          }
          
          /// @title GnosisSafeProxy - Generic proxy contract allows to execute all transactions applying the code of a master contract.
          /// @author Stefan George - <[email protected]>
          /// @author Richard Meissner - <[email protected]>
          contract GnosisSafeProxy {
              // singleton always needs to be first declared variable, to ensure that it is at the same location in the contracts to which calls are delegated.
              // To reduce deployment costs this variable is internal and needs to be retrieved via `getStorageAt`
              address internal singleton;
          
              /// @dev Constructor function sets address of singleton contract.
              /// @param _singleton Singleton address.
              constructor(address _singleton) {
                  require(_singleton != address(0), "Invalid singleton address provided");
                  singleton = _singleton;
              }
          
              /// @dev Fallback function forwards all transactions and returns all received return data.
              fallback() external payable {
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      let _singleton := and(sload(0), 0xffffffffffffffffffffffffffffffffffffffff)
                      // 0xa619486e == keccak("masterCopy()"). The value is right padded to 32-bytes with 0s
                      if eq(calldataload(0), 0xa619486e00000000000000000000000000000000000000000000000000000000) {
                          mstore(0, _singleton)
                          return(0, 0x20)
                      }
                      calldatacopy(0, 0, calldatasize())
                      let success := delegatecall(gas(), _singleton, 0, calldatasize(), 0, 0)
                      returndatacopy(0, 0, returndatasize())
                      if eq(success, 0) {
                          revert(0, returndatasize())
                      }
                      return(0, returndatasize())
                  }
              }
          }
          
          /// @title Proxy Factory - Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
          /// @author Stefan George - <[email protected]>
          contract GnosisSafeProxyFactory {
              event ProxyCreation(GnosisSafeProxy proxy, address singleton);
          
              /// @dev Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
              /// @param singleton Address of singleton contract.
              /// @param data Payload for message call sent to new proxy contract.
              function createProxy(address singleton, bytes memory data) public returns (GnosisSafeProxy proxy) {
                  proxy = new GnosisSafeProxy(singleton);
                  if (data.length > 0)
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          if eq(call(gas(), proxy, 0, add(data, 0x20), mload(data), 0, 0), 0) {
                              revert(0, 0)
                          }
                      }
                  emit ProxyCreation(proxy, singleton);
              }
          
              /// @dev Allows to retrieve the runtime code of a deployed Proxy. This can be used to check that the expected Proxy was deployed.
              function proxyRuntimeCode() public pure returns (bytes memory) {
                  return type(GnosisSafeProxy).runtimeCode;
              }
          
              /// @dev Allows to retrieve the creation code used for the Proxy deployment. With this it is easily possible to calculate predicted address.
              function proxyCreationCode() public pure returns (bytes memory) {
                  return type(GnosisSafeProxy).creationCode;
              }
          
              /// @dev Allows to create new proxy contact using CREATE2 but it doesn't run the initializer.
              ///      This method is only meant as an utility to be called from other methods
              /// @param _singleton Address of singleton contract.
              /// @param initializer Payload for message call sent to new proxy contract.
              /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
              function deployProxyWithNonce(
                  address _singleton,
                  bytes memory initializer,
                  uint256 saltNonce
              ) internal returns (GnosisSafeProxy proxy) {
                  // If the initializer changes the proxy address should change too. Hashing the initializer data is cheaper than just concatinating it
                  bytes32 salt = keccak256(abi.encodePacked(keccak256(initializer), saltNonce));
                  bytes memory deploymentData = abi.encodePacked(type(GnosisSafeProxy).creationCode, uint256(uint160(_singleton)));
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      proxy := create2(0x0, add(0x20, deploymentData), mload(deploymentData), salt)
                  }
                  require(address(proxy) != address(0), "Create2 call failed");
              }
          
              /// @dev Allows to create new proxy contact and execute a message call to the new proxy within one transaction.
              /// @param _singleton Address of singleton contract.
              /// @param initializer Payload for message call sent to new proxy contract.
              /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
              function createProxyWithNonce(
                  address _singleton,
                  bytes memory initializer,
                  uint256 saltNonce
              ) public returns (GnosisSafeProxy proxy) {
                  proxy = deployProxyWithNonce(_singleton, initializer, saltNonce);
                  if (initializer.length > 0)
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          if eq(call(gas(), proxy, 0, add(initializer, 0x20), mload(initializer), 0, 0), 0) {
                              revert(0, 0)
                          }
                      }
                  emit ProxyCreation(proxy, _singleton);
              }
          
              /// @dev Allows to create new proxy contact, execute a message call to the new proxy and call a specified callback within one transaction
              /// @param _singleton Address of singleton contract.
              /// @param initializer Payload for message call sent to new proxy contract.
              /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
              /// @param callback Callback that will be invoced after the new proxy contract has been successfully deployed and initialized.
              function createProxyWithCallback(
                  address _singleton,
                  bytes memory initializer,
                  uint256 saltNonce,
                  IProxyCreationCallback callback
              ) public returns (GnosisSafeProxy proxy) {
                  uint256 saltNonceWithCallback = uint256(keccak256(abi.encodePacked(saltNonce, callback)));
                  proxy = createProxyWithNonce(_singleton, initializer, saltNonceWithCallback);
                  if (address(callback) != address(0)) callback.proxyCreated(proxy, _singleton, initializer, saltNonce);
              }
          
              /// @dev Allows to get the address for a new proxy contact created via `createProxyWithNonce`
              ///      This method is only meant for address calculation purpose when you use an initializer that would revert,
              ///      therefore the response is returned with a revert. When calling this method set `from` to the address of the proxy factory.
              /// @param _singleton Address of singleton contract.
              /// @param initializer Payload for message call sent to new proxy contract.
              /// @param saltNonce Nonce that will be used to generate the salt to calculate the address of the new proxy contract.
              function calculateCreateProxyWithNonceAddress(
                  address _singleton,
                  bytes calldata initializer,
                  uint256 saltNonce
              ) external returns (GnosisSafeProxy proxy) {
                  proxy = deployProxyWithNonce(_singleton, initializer, saltNonce);
                  revert(string(abi.encodePacked(proxy)));
              }
          }
          
          interface IProxyCreationCallback {
              function proxyCreated(
                  GnosisSafeProxy proxy,
                  address _singleton,
                  bytes calldata initializer,
                  uint256 saltNonce
              ) external;
          }

          File 2 of 6: TetherToken
          pragma solidity ^0.4.17;
          
          /**
           * @title SafeMath
           * @dev Math operations with safety checks that throw on error
           */
          library SafeMath {
              function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                  if (a == 0) {
                      return 0;
                  }
                  uint256 c = a * b;
                  assert(c / a == b);
                  return c;
              }
          
              function div(uint256 a, uint256 b) internal pure returns (uint256) {
                  // assert(b > 0); // Solidity automatically throws when dividing by 0
                  uint256 c = a / b;
                  // assert(a == b * c + a % b); // There is no case in which this doesn't hold
                  return c;
              }
          
              function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                  assert(b <= a);
                  return a - b;
              }
          
              function add(uint256 a, uint256 b) internal pure returns (uint256) {
                  uint256 c = a + b;
                  assert(c >= a);
                  return c;
              }
          }
          
          /**
           * @title Ownable
           * @dev The Ownable contract has an owner address, and provides basic authorization control
           * functions, this simplifies the implementation of "user permissions".
           */
          contract Ownable {
              address public owner;
          
              /**
                * @dev The Ownable constructor sets the original `owner` of the contract to the sender
                * account.
                */
              function Ownable() public {
                  owner = msg.sender;
              }
          
              /**
                * @dev Throws if called by any account other than the owner.
                */
              modifier onlyOwner() {
                  require(msg.sender == owner);
                  _;
              }
          
              /**
              * @dev Allows the current owner to transfer control of the contract to a newOwner.
              * @param newOwner The address to transfer ownership to.
              */
              function transferOwnership(address newOwner) public onlyOwner {
                  if (newOwner != address(0)) {
                      owner = newOwner;
                  }
              }
          
          }
          
          /**
           * @title ERC20Basic
           * @dev Simpler version of ERC20 interface
           * @dev see https://github.com/ethereum/EIPs/issues/20
           */
          contract ERC20Basic {
              uint public _totalSupply;
              function totalSupply() public constant returns (uint);
              function balanceOf(address who) public constant returns (uint);
              function transfer(address to, uint value) public;
              event Transfer(address indexed from, address indexed to, uint value);
          }
          
          /**
           * @title ERC20 interface
           * @dev see https://github.com/ethereum/EIPs/issues/20
           */
          contract ERC20 is ERC20Basic {
              function allowance(address owner, address spender) public constant returns (uint);
              function transferFrom(address from, address to, uint value) public;
              function approve(address spender, uint value) public;
              event Approval(address indexed owner, address indexed spender, uint value);
          }
          
          /**
           * @title Basic token
           * @dev Basic version of StandardToken, with no allowances.
           */
          contract BasicToken is Ownable, ERC20Basic {
              using SafeMath for uint;
          
              mapping(address => uint) public balances;
          
              // additional variables for use if transaction fees ever became necessary
              uint public basisPointsRate = 0;
              uint public maximumFee = 0;
          
              /**
              * @dev Fix for the ERC20 short address attack.
              */
              modifier onlyPayloadSize(uint size) {
                  require(!(msg.data.length < size + 4));
                  _;
              }
          
              /**
              * @dev transfer token for a specified address
              * @param _to The address to transfer to.
              * @param _value The amount to be transferred.
              */
              function transfer(address _to, uint _value) public onlyPayloadSize(2 * 32) {
                  uint fee = (_value.mul(basisPointsRate)).div(10000);
                  if (fee > maximumFee) {
                      fee = maximumFee;
                  }
                  uint sendAmount = _value.sub(fee);
                  balances[msg.sender] = balances[msg.sender].sub(_value);
                  balances[_to] = balances[_to].add(sendAmount);
                  if (fee > 0) {
                      balances[owner] = balances[owner].add(fee);
                      Transfer(msg.sender, owner, fee);
                  }
                  Transfer(msg.sender, _to, sendAmount);
              }
          
              /**
              * @dev Gets the balance of the specified address.
              * @param _owner The address to query the the balance of.
              * @return An uint representing the amount owned by the passed address.
              */
              function balanceOf(address _owner) public constant returns (uint balance) {
                  return balances[_owner];
              }
          
          }
          
          /**
           * @title Standard ERC20 token
           *
           * @dev Implementation of the basic standard token.
           * @dev https://github.com/ethereum/EIPs/issues/20
           * @dev Based oncode by FirstBlood: https://github.com/Firstbloodio/token/blob/master/smart_contract/FirstBloodToken.sol
           */
          contract StandardToken is BasicToken, ERC20 {
          
              mapping (address => mapping (address => uint)) public allowed;
          
              uint public constant MAX_UINT = 2**256 - 1;
          
              /**
              * @dev Transfer tokens from one address to another
              * @param _from address The address which you want to send tokens from
              * @param _to address The address which you want to transfer to
              * @param _value uint the amount of tokens to be transferred
              */
              function transferFrom(address _from, address _to, uint _value) public onlyPayloadSize(3 * 32) {
                  var _allowance = allowed[_from][msg.sender];
          
                  // Check is not needed because sub(_allowance, _value) will already throw if this condition is not met
                  // if (_value > _allowance) throw;
          
                  uint fee = (_value.mul(basisPointsRate)).div(10000);
                  if (fee > maximumFee) {
                      fee = maximumFee;
                  }
                  if (_allowance < MAX_UINT) {
                      allowed[_from][msg.sender] = _allowance.sub(_value);
                  }
                  uint sendAmount = _value.sub(fee);
                  balances[_from] = balances[_from].sub(_value);
                  balances[_to] = balances[_to].add(sendAmount);
                  if (fee > 0) {
                      balances[owner] = balances[owner].add(fee);
                      Transfer(_from, owner, fee);
                  }
                  Transfer(_from, _to, sendAmount);
              }
          
              /**
              * @dev Approve the passed address to spend the specified amount of tokens on behalf of msg.sender.
              * @param _spender The address which will spend the funds.
              * @param _value The amount of tokens to be spent.
              */
              function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
          
                  // To change the approve amount you first have to reduce the addresses`
                  //  allowance to zero by calling `approve(_spender, 0)` if it is not
                  //  already 0 to mitigate the race condition described here:
                  //  https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
                  require(!((_value != 0) && (allowed[msg.sender][_spender] != 0)));
          
                  allowed[msg.sender][_spender] = _value;
                  Approval(msg.sender, _spender, _value);
              }
          
              /**
              * @dev Function to check the amount of tokens than an owner allowed to a spender.
              * @param _owner address The address which owns the funds.
              * @param _spender address The address which will spend the funds.
              * @return A uint specifying the amount of tokens still available for the spender.
              */
              function allowance(address _owner, address _spender) public constant returns (uint remaining) {
                  return allowed[_owner][_spender];
              }
          
          }
          
          
          /**
           * @title Pausable
           * @dev Base contract which allows children to implement an emergency stop mechanism.
           */
          contract Pausable is Ownable {
            event Pause();
            event Unpause();
          
            bool public paused = false;
          
          
            /**
             * @dev Modifier to make a function callable only when the contract is not paused.
             */
            modifier whenNotPaused() {
              require(!paused);
              _;
            }
          
            /**
             * @dev Modifier to make a function callable only when the contract is paused.
             */
            modifier whenPaused() {
              require(paused);
              _;
            }
          
            /**
             * @dev called by the owner to pause, triggers stopped state
             */
            function pause() onlyOwner whenNotPaused public {
              paused = true;
              Pause();
            }
          
            /**
             * @dev called by the owner to unpause, returns to normal state
             */
            function unpause() onlyOwner whenPaused public {
              paused = false;
              Unpause();
            }
          }
          
          contract BlackList is Ownable, BasicToken {
          
              /////// Getters to allow the same blacklist to be used also by other contracts (including upgraded Tether) ///////
              function getBlackListStatus(address _maker) external constant returns (bool) {
                  return isBlackListed[_maker];
              }
          
              function getOwner() external constant returns (address) {
                  return owner;
              }
          
              mapping (address => bool) public isBlackListed;
              
              function addBlackList (address _evilUser) public onlyOwner {
                  isBlackListed[_evilUser] = true;
                  AddedBlackList(_evilUser);
              }
          
              function removeBlackList (address _clearedUser) public onlyOwner {
                  isBlackListed[_clearedUser] = false;
                  RemovedBlackList(_clearedUser);
              }
          
              function destroyBlackFunds (address _blackListedUser) public onlyOwner {
                  require(isBlackListed[_blackListedUser]);
                  uint dirtyFunds = balanceOf(_blackListedUser);
                  balances[_blackListedUser] = 0;
                  _totalSupply -= dirtyFunds;
                  DestroyedBlackFunds(_blackListedUser, dirtyFunds);
              }
          
              event DestroyedBlackFunds(address _blackListedUser, uint _balance);
          
              event AddedBlackList(address _user);
          
              event RemovedBlackList(address _user);
          
          }
          
          contract UpgradedStandardToken is StandardToken{
              // those methods are called by the legacy contract
              // and they must ensure msg.sender to be the contract address
              function transferByLegacy(address from, address to, uint value) public;
              function transferFromByLegacy(address sender, address from, address spender, uint value) public;
              function approveByLegacy(address from, address spender, uint value) public;
          }
          
          contract TetherToken is Pausable, StandardToken, BlackList {
          
              string public name;
              string public symbol;
              uint public decimals;
              address public upgradedAddress;
              bool public deprecated;
          
              //  The contract can be initialized with a number of tokens
              //  All the tokens are deposited to the owner address
              //
              // @param _balance Initial supply of the contract
              // @param _name Token Name
              // @param _symbol Token symbol
              // @param _decimals Token decimals
              function TetherToken(uint _initialSupply, string _name, string _symbol, uint _decimals) public {
                  _totalSupply = _initialSupply;
                  name = _name;
                  symbol = _symbol;
                  decimals = _decimals;
                  balances[owner] = _initialSupply;
                  deprecated = false;
              }
          
              // Forward ERC20 methods to upgraded contract if this one is deprecated
              function transfer(address _to, uint _value) public whenNotPaused {
                  require(!isBlackListed[msg.sender]);
                  if (deprecated) {
                      return UpgradedStandardToken(upgradedAddress).transferByLegacy(msg.sender, _to, _value);
                  } else {
                      return super.transfer(_to, _value);
                  }
              }
          
              // Forward ERC20 methods to upgraded contract if this one is deprecated
              function transferFrom(address _from, address _to, uint _value) public whenNotPaused {
                  require(!isBlackListed[_from]);
                  if (deprecated) {
                      return UpgradedStandardToken(upgradedAddress).transferFromByLegacy(msg.sender, _from, _to, _value);
                  } else {
                      return super.transferFrom(_from, _to, _value);
                  }
              }
          
              // Forward ERC20 methods to upgraded contract if this one is deprecated
              function balanceOf(address who) public constant returns (uint) {
                  if (deprecated) {
                      return UpgradedStandardToken(upgradedAddress).balanceOf(who);
                  } else {
                      return super.balanceOf(who);
                  }
              }
          
              // Forward ERC20 methods to upgraded contract if this one is deprecated
              function approve(address _spender, uint _value) public onlyPayloadSize(2 * 32) {
                  if (deprecated) {
                      return UpgradedStandardToken(upgradedAddress).approveByLegacy(msg.sender, _spender, _value);
                  } else {
                      return super.approve(_spender, _value);
                  }
              }
          
              // Forward ERC20 methods to upgraded contract if this one is deprecated
              function allowance(address _owner, address _spender) public constant returns (uint remaining) {
                  if (deprecated) {
                      return StandardToken(upgradedAddress).allowance(_owner, _spender);
                  } else {
                      return super.allowance(_owner, _spender);
                  }
              }
          
              // deprecate current contract in favour of a new one
              function deprecate(address _upgradedAddress) public onlyOwner {
                  deprecated = true;
                  upgradedAddress = _upgradedAddress;
                  Deprecate(_upgradedAddress);
              }
          
              // deprecate current contract if favour of a new one
              function totalSupply() public constant returns (uint) {
                  if (deprecated) {
                      return StandardToken(upgradedAddress).totalSupply();
                  } else {
                      return _totalSupply;
                  }
              }
          
              // Issue a new amount of tokens
              // these tokens are deposited into the owner address
              //
              // @param _amount Number of tokens to be issued
              function issue(uint amount) public onlyOwner {
                  require(_totalSupply + amount > _totalSupply);
                  require(balances[owner] + amount > balances[owner]);
          
                  balances[owner] += amount;
                  _totalSupply += amount;
                  Issue(amount);
              }
          
              // Redeem tokens.
              // These tokens are withdrawn from the owner address
              // if the balance must be enough to cover the redeem
              // or the call will fail.
              // @param _amount Number of tokens to be issued
              function redeem(uint amount) public onlyOwner {
                  require(_totalSupply >= amount);
                  require(balances[owner] >= amount);
          
                  _totalSupply -= amount;
                  balances[owner] -= amount;
                  Redeem(amount);
              }
          
              function setParams(uint newBasisPoints, uint newMaxFee) public onlyOwner {
                  // Ensure transparency by hardcoding limit beyond which fees can never be added
                  require(newBasisPoints < 20);
                  require(newMaxFee < 50);
          
                  basisPointsRate = newBasisPoints;
                  maximumFee = newMaxFee.mul(10**decimals);
          
                  Params(basisPointsRate, maximumFee);
              }
          
              // Called when new token are issued
              event Issue(uint amount);
          
              // Called when tokens are redeemed
              event Redeem(uint amount);
          
              // Called when contract is deprecated
              event Deprecate(address newAddress);
          
              // Called if contract ever adds fees
              event Params(uint feeBasisPoints, uint maxFee);
          }

          File 3 of 6: ERC1967Proxy
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          import "@openzeppelin/contracts/proxy/beacon/BeaconProxy.sol";
          import "@openzeppelin/contracts/proxy/beacon/UpgradeableBeacon.sol";
          import "@openzeppelin/contracts/proxy/ERC1967/ERC1967Proxy.sol";
          import "@openzeppelin/contracts/proxy/transparent/TransparentUpgradeableProxy.sol";
          import "@openzeppelin/contracts/proxy/transparent/ProxyAdmin.sol";
          // Kept for backwards compatibility with older versions of Hardhat and Truffle plugins.
          contract AdminUpgradeabilityProxy is TransparentUpgradeableProxy {
              constructor(address logic, address admin, bytes memory data) payable TransparentUpgradeableProxy(logic, admin, data) {}
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          import "./IBeacon.sol";
          import "../Proxy.sol";
          import "../ERC1967/ERC1967Upgrade.sol";
          /**
           * @dev This contract implements a proxy that gets the implementation address for each call from a {UpgradeableBeacon}.
           *
           * The beacon address is stored in storage slot `uint256(keccak256('eip1967.proxy.beacon')) - 1`, so that it doesn't
           * conflict with the storage layout of the implementation behind the proxy.
           *
           * _Available since v3.4._
           */
          contract BeaconProxy is Proxy, ERC1967Upgrade {
              /**
               * @dev Initializes the proxy with `beacon`.
               *
               * If `data` is nonempty, it's used as data in a delegate call to the implementation returned by the beacon. This
               * will typically be an encoded function call, and allows initializating the storage of the proxy like a Solidity
               * constructor.
               *
               * Requirements:
               *
               * - `beacon` must be a contract with the interface {IBeacon}.
               */
              constructor(address beacon, bytes memory data) payable {
                  assert(_BEACON_SLOT == bytes32(uint256(keccak256("eip1967.proxy.beacon")) - 1));
                  _upgradeBeaconToAndCall(beacon, data, false);
              }
              /**
               * @dev Returns the current beacon address.
               */
              function _beacon() internal view virtual returns (address) {
                  return _getBeacon();
              }
              /**
               * @dev Returns the current implementation address of the associated beacon.
               */
              function _implementation() internal view virtual override returns (address) {
                  return IBeacon(_getBeacon()).implementation();
              }
              /**
               * @dev Changes the proxy to use a new beacon. Deprecated: see {_upgradeBeaconToAndCall}.
               *
               * If `data` is nonempty, it's used as data in a delegate call to the implementation returned by the beacon.
               *
               * Requirements:
               *
               * - `beacon` must be a contract.
               * - The implementation returned by `beacon` must be a contract.
               */
              function _setBeacon(address beacon, bytes memory data) internal virtual {
                  _upgradeBeaconToAndCall(beacon, data, false);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          import "./IBeacon.sol";
          import "../../access/Ownable.sol";
          import "../../utils/Address.sol";
          /**
           * @dev This contract is used in conjunction with one or more instances of {BeaconProxy} to determine their
           * implementation contract, which is where they will delegate all function calls.
           *
           * An owner is able to change the implementation the beacon points to, thus upgrading the proxies that use this beacon.
           */
          contract UpgradeableBeacon is IBeacon, Ownable {
              address private _implementation;
              /**
               * @dev Emitted when the implementation returned by the beacon is changed.
               */
              event Upgraded(address indexed implementation);
              /**
               * @dev Sets the address of the initial implementation, and the deployer account as the owner who can upgrade the
               * beacon.
               */
              constructor(address implementation_) {
                  _setImplementation(implementation_);
              }
              /**
               * @dev Returns the current implementation address.
               */
              function implementation() public view virtual override returns (address) {
                  return _implementation;
              }
              /**
               * @dev Upgrades the beacon to a new implementation.
               *
               * Emits an {Upgraded} event.
               *
               * Requirements:
               *
               * - msg.sender must be the owner of the contract.
               * - `newImplementation` must be a contract.
               */
              function upgradeTo(address newImplementation) public virtual onlyOwner {
                  _setImplementation(newImplementation);
                  emit Upgraded(newImplementation);
              }
              /**
               * @dev Sets the implementation contract address for this beacon
               *
               * Requirements:
               *
               * - `newImplementation` must be a contract.
               */
              function _setImplementation(address newImplementation) private {
                  require(Address.isContract(newImplementation), "UpgradeableBeacon: implementation is not a contract");
                  _implementation = newImplementation;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          import "../Proxy.sol";
          import "./ERC1967Upgrade.sol";
          /**
           * @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
           * implementation address that can be changed. This address is stored in storage in the location specified by
           * https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
           * implementation behind the proxy.
           */
          contract ERC1967Proxy is Proxy, ERC1967Upgrade {
              /**
               * @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
               *
               * If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
               * function call, and allows initializating the storage of the proxy like a Solidity constructor.
               */
              constructor(address _logic, bytes memory _data) payable {
                  assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
                  _upgradeToAndCall(_logic, _data, false);
              }
              /**
               * @dev Returns the current implementation address.
               */
              function _implementation() internal view virtual override returns (address impl) {
                  return ERC1967Upgrade._getImplementation();
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          import "../ERC1967/ERC1967Proxy.sol";
          /**
           * @dev This contract implements a proxy that is upgradeable by an admin.
           *
           * To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
           * clashing], which can potentially be used in an attack, this contract uses the
           * https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
           * things that go hand in hand:
           *
           * 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
           * that call matches one of the admin functions exposed by the proxy itself.
           * 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
           * implementation. If the admin tries to call a function on the implementation it will fail with an error that says
           * "admin cannot fallback to proxy target".
           *
           * These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
           * the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
           * to sudden errors when trying to call a function from the proxy implementation.
           *
           * Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
           * you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
           */
          contract TransparentUpgradeableProxy is ERC1967Proxy {
              /**
               * @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
               * optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
               */
              constructor(address _logic, address admin_, bytes memory _data) payable ERC1967Proxy(_logic, _data) {
                  assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
                  _changeAdmin(admin_);
              }
              /**
               * @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
               */
              modifier ifAdmin() {
                  if (msg.sender == _getAdmin()) {
                      _;
                  } else {
                      _fallback();
                  }
              }
              /**
               * @dev Returns the current admin.
               *
               * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
               *
               * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
               * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
               * `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
               */
              function admin() external ifAdmin returns (address admin_) {
                  admin_ = _getAdmin();
              }
              /**
               * @dev Returns the current implementation.
               *
               * NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
               *
               * TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
               * https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
               * `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
               */
              function implementation() external ifAdmin returns (address implementation_) {
                  implementation_ = _implementation();
              }
              /**
               * @dev Changes the admin of the proxy.
               *
               * Emits an {AdminChanged} event.
               *
               * NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
               */
              function changeAdmin(address newAdmin) external virtual ifAdmin {
                  _changeAdmin(newAdmin);
              }
              /**
               * @dev Upgrade the implementation of the proxy.
               *
               * NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
               */
              function upgradeTo(address newImplementation) external ifAdmin {
                  _upgradeToAndCall(newImplementation, bytes(""), false);
              }
              /**
               * @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
               * by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
               * proxied contract.
               *
               * NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
               */
              function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
                  _upgradeToAndCall(newImplementation, data, true);
              }
              /**
               * @dev Returns the current admin.
               */
              function _admin() internal view virtual returns (address) {
                  return _getAdmin();
              }
              /**
               * @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
               */
              function _beforeFallback() internal virtual override {
                  require(msg.sender != _getAdmin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
                  super._beforeFallback();
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          import "./TransparentUpgradeableProxy.sol";
          import "../../access/Ownable.sol";
          /**
           * @dev This is an auxiliary contract meant to be assigned as the admin of a {TransparentUpgradeableProxy}. For an
           * explanation of why you would want to use this see the documentation for {TransparentUpgradeableProxy}.
           */
          contract ProxyAdmin is Ownable {
              /**
               * @dev Returns the current implementation of `proxy`.
               *
               * Requirements:
               *
               * - This contract must be the admin of `proxy`.
               */
              function getProxyImplementation(TransparentUpgradeableProxy proxy) public view virtual returns (address) {
                  // We need to manually run the static call since the getter cannot be flagged as view
                  // bytes4(keccak256("implementation()")) == 0x5c60da1b
                  (bool success, bytes memory returndata) = address(proxy).staticcall(hex"5c60da1b");
                  require(success);
                  return abi.decode(returndata, (address));
              }
              /**
               * @dev Returns the current admin of `proxy`.
               *
               * Requirements:
               *
               * - This contract must be the admin of `proxy`.
               */
              function getProxyAdmin(TransparentUpgradeableProxy proxy) public view virtual returns (address) {
                  // We need to manually run the static call since the getter cannot be flagged as view
                  // bytes4(keccak256("admin()")) == 0xf851a440
                  (bool success, bytes memory returndata) = address(proxy).staticcall(hex"f851a440");
                  require(success);
                  return abi.decode(returndata, (address));
              }
              /**
               * @dev Changes the admin of `proxy` to `newAdmin`.
               *
               * Requirements:
               *
               * - This contract must be the current admin of `proxy`.
               */
              function changeProxyAdmin(TransparentUpgradeableProxy proxy, address newAdmin) public virtual onlyOwner {
                  proxy.changeAdmin(newAdmin);
              }
              /**
               * @dev Upgrades `proxy` to `implementation`. See {TransparentUpgradeableProxy-upgradeTo}.
               *
               * Requirements:
               *
               * - This contract must be the admin of `proxy`.
               */
              function upgrade(TransparentUpgradeableProxy proxy, address implementation) public virtual onlyOwner {
                  proxy.upgradeTo(implementation);
              }
              /**
               * @dev Upgrades `proxy` to `implementation` and calls a function on the new implementation. See
               * {TransparentUpgradeableProxy-upgradeToAndCall}.
               *
               * Requirements:
               *
               * - This contract must be the admin of `proxy`.
               */
              function upgradeAndCall(TransparentUpgradeableProxy proxy, address implementation, bytes memory data) public payable virtual onlyOwner {
                  proxy.upgradeToAndCall{value: msg.value}(implementation, data);
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          /**
           * @dev This is the interface that {BeaconProxy} expects of its beacon.
           */
          interface IBeacon {
              /**
               * @dev Must return an address that can be used as a delegate call target.
               *
               * {BeaconProxy} will check that this address is a contract.
               */
              function implementation() external view returns (address);
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          /**
           * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
           * instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
           * be specified by overriding the virtual {_implementation} function.
           *
           * Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
           * different contract through the {_delegate} function.
           *
           * The success and return data of the delegated call will be returned back to the caller of the proxy.
           */
          abstract contract Proxy {
              /**
               * @dev Delegates the current call to `implementation`.
               *
               * This function does not return to its internall call site, it will return directly to the external caller.
               */
              function _delegate(address implementation) internal virtual {
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      // Copy msg.data. We take full control of memory in this inline assembly
                      // block because it will not return to Solidity code. We overwrite the
                      // Solidity scratch pad at memory position 0.
                      calldatacopy(0, 0, calldatasize())
                      // Call the implementation.
                      // out and outsize are 0 because we don't know the size yet.
                      let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
                      // Copy the returned data.
                      returndatacopy(0, 0, returndatasize())
                      switch result
                      // delegatecall returns 0 on error.
                      case 0 { revert(0, returndatasize()) }
                      default { return(0, returndatasize()) }
                  }
              }
              /**
               * @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
               * and {_fallback} should delegate.
               */
              function _implementation() internal view virtual returns (address);
              /**
               * @dev Delegates the current call to the address returned by `_implementation()`.
               *
               * This function does not return to its internall call site, it will return directly to the external caller.
               */
              function _fallback() internal virtual {
                  _beforeFallback();
                  _delegate(_implementation());
              }
              /**
               * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
               * function in the contract matches the call data.
               */
              fallback () external payable virtual {
                  _fallback();
              }
              /**
               * @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
               * is empty.
               */
              receive () external payable virtual {
                  _fallback();
              }
              /**
               * @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
               * call, or as part of the Solidity `fallback` or `receive` functions.
               *
               * If overriden should call `super._beforeFallback()`.
               */
              function _beforeFallback() internal virtual {
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.2;
          import "../beacon/IBeacon.sol";
          import "../../utils/Address.sol";
          import "../../utils/StorageSlot.sol";
          /**
           * @dev This abstract contract provides getters and event emitting update functions for
           * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
           *
           * _Available since v4.1._
           *
           * @custom:oz-upgrades-unsafe-allow delegatecall
           */
          abstract contract ERC1967Upgrade {
              // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
              bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
              /**
               * @dev Storage slot with the address of the current implementation.
               * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
              /**
               * @dev Emitted when the implementation is upgraded.
               */
              event Upgraded(address indexed implementation);
              /**
               * @dev Returns the current implementation address.
               */
              function _getImplementation() internal view returns (address) {
                  return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
              }
              /**
               * @dev Stores a new address in the EIP1967 implementation slot.
               */
              function _setImplementation(address newImplementation) private {
                  require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                  StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
              }
              /**
               * @dev Perform implementation upgrade
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeTo(address newImplementation) internal {
                  _setImplementation(newImplementation);
                  emit Upgraded(newImplementation);
              }
              /**
               * @dev Perform implementation upgrade with additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCall(address newImplementation, bytes memory data, bool forceCall) internal {
                  _setImplementation(newImplementation);
                  emit Upgraded(newImplementation);
                  if (data.length > 0 || forceCall) {
                      Address.functionDelegateCall(newImplementation, data);
                  }
              }
              /**
               * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCallSecure(address newImplementation, bytes memory data, bool forceCall) internal {
                  address oldImplementation = _getImplementation();
                  // Initial upgrade and setup call
                  _setImplementation(newImplementation);
                  if (data.length > 0 || forceCall) {
                      Address.functionDelegateCall(newImplementation, data);
                  }
                  // Perform rollback test if not already in progress
                  StorageSlot.BooleanSlot storage rollbackTesting = StorageSlot.getBooleanSlot(_ROLLBACK_SLOT);
                  if (!rollbackTesting.value) {
                      // Trigger rollback using upgradeTo from the new implementation
                      rollbackTesting.value = true;
                      Address.functionDelegateCall(
                          newImplementation,
                          abi.encodeWithSignature(
                              "upgradeTo(address)",
                              oldImplementation
                          )
                      );
                      rollbackTesting.value = false;
                      // Check rollback was effective
                      require(oldImplementation == _getImplementation(), "ERC1967Upgrade: upgrade breaks further upgrades");
                      // Finally reset to the new implementation and log the upgrade
                      _setImplementation(newImplementation);
                      emit Upgraded(newImplementation);
                  }
              }
              /**
               * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
               * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
               *
               * Emits a {BeaconUpgraded} event.
               */
              function _upgradeBeaconToAndCall(address newBeacon, bytes memory data, bool forceCall) internal {
                  _setBeacon(newBeacon);
                  emit BeaconUpgraded(newBeacon);
                  if (data.length > 0 || forceCall) {
                      Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
                  }
              }
              /**
               * @dev Storage slot with the admin of the contract.
               * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
              /**
               * @dev Emitted when the admin account has changed.
               */
              event AdminChanged(address previousAdmin, address newAdmin);
              /**
               * @dev Returns the current admin.
               */
              function _getAdmin() internal view returns (address) {
                  return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
              }
              /**
               * @dev Stores a new address in the EIP1967 admin slot.
               */
              function _setAdmin(address newAdmin) private {
                  require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                  StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
              }
              /**
               * @dev Changes the admin of the proxy.
               *
               * Emits an {AdminChanged} event.
               */
              function _changeAdmin(address newAdmin) internal {
                  emit AdminChanged(_getAdmin(), newAdmin);
                  _setAdmin(newAdmin);
              }
              /**
               * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
               * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
               */
              bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
              /**
               * @dev Emitted when the beacon is upgraded.
               */
              event BeaconUpgraded(address indexed beacon);
              /**
               * @dev Returns the current beacon.
               */
              function _getBeacon() internal view returns (address) {
                  return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
              }
              /**
               * @dev Stores a new beacon in the EIP1967 beacon slot.
               */
              function _setBeacon(address newBeacon) private {
                  require(
                      Address.isContract(newBeacon),
                      "ERC1967: new beacon is not a contract"
                  );
                  require(
                      Address.isContract(IBeacon(newBeacon).implementation()),
                      "ERC1967: beacon implementation is not a contract"
                  );
                  StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          /**
           * @dev Collection of functions related to the address type
           */
          library Address {
              /**
               * @dev Returns true if `account` is a contract.
               *
               * [IMPORTANT]
               * ====
               * It is unsafe to assume that an address for which this function returns
               * false is an externally-owned account (EOA) and not a contract.
               *
               * Among others, `isContract` will return false for the following
               * types of addresses:
               *
               *  - an externally-owned account
               *  - a contract in construction
               *  - an address where a contract will be created
               *  - an address where a contract lived, but was destroyed
               * ====
               */
              function isContract(address account) internal view returns (bool) {
                  // This method relies on extcodesize, which returns 0 for contracts in
                  // construction, since the code is only stored at the end of the
                  // constructor execution.
                  uint256 size;
                  // solhint-disable-next-line no-inline-assembly
                  assembly { size := extcodesize(account) }
                  return size > 0;
              }
              /**
               * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
               * `recipient`, forwarding all available gas and reverting on errors.
               *
               * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
               * of certain opcodes, possibly making contracts go over the 2300 gas limit
               * imposed by `transfer`, making them unable to receive funds via
               * `transfer`. {sendValue} removes this limitation.
               *
               * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
               *
               * IMPORTANT: because control is transferred to `recipient`, care must be
               * taken to not create reentrancy vulnerabilities. Consider using
               * {ReentrancyGuard} or the
               * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
               */
              function sendValue(address payable recipient, uint256 amount) internal {
                  require(address(this).balance >= amount, "Address: insufficient balance");
                  // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
                  (bool success, ) = recipient.call{ value: amount }("");
                  require(success, "Address: unable to send value, recipient may have reverted");
              }
              /**
               * @dev Performs a Solidity function call using a low level `call`. A
               * plain`call` is an unsafe replacement for a function call: use this
               * function instead.
               *
               * If `target` reverts with a revert reason, it is bubbled up by this
               * function (like regular Solidity function calls).
               *
               * Returns the raw returned data. To convert to the expected return value,
               * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
               *
               * Requirements:
               *
               * - `target` must be a contract.
               * - calling `target` with `data` must not revert.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                return functionCall(target, data, "Address: low-level call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
               * `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but also transferring `value` wei to `target`.
               *
               * Requirements:
               *
               * - the calling contract must have an ETH balance of at least `value`.
               * - the called Solidity function must be `payable`.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
              }
              /**
               * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
               * with `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
                  require(address(this).balance >= value, "Address: insufficient balance for call");
                  require(isContract(target), "Address: call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.call{ value: value }(data);
                  return _verifyCallResult(success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                  return functionStaticCall(target, data, "Address: low-level static call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
                  require(isContract(target), "Address: static call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.staticcall(data);
                  return _verifyCallResult(success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionDelegateCall(target, data, "Address: low-level delegate call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
                  require(isContract(target), "Address: delegate call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.delegatecall(data);
                  return _verifyCallResult(success, returndata, errorMessage);
              }
              function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
                  if (success) {
                      return returndata;
                  } else {
                      // Look for revert reason and bubble it up if present
                      if (returndata.length > 0) {
                          // The easiest way to bubble the revert reason is using memory via assembly
                          // solhint-disable-next-line no-inline-assembly
                          assembly {
                              let returndata_size := mload(returndata)
                              revert(add(32, returndata), returndata_size)
                          }
                      } else {
                          revert(errorMessage);
                      }
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          /**
           * @dev Library for reading and writing primitive types to specific storage slots.
           *
           * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
           * This library helps with reading and writing to such slots without the need for inline assembly.
           *
           * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
           *
           * Example usage to set ERC1967 implementation slot:
           * ```
           * contract ERC1967 {
           *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
           *
           *     function _getImplementation() internal view returns (address) {
           *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
           *     }
           *
           *     function _setImplementation(address newImplementation) internal {
           *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
           *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
           *     }
           * }
           * ```
           *
           * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
           */
          library StorageSlot {
              struct AddressSlot {
                  address value;
              }
              struct BooleanSlot {
                  bool value;
              }
              struct Bytes32Slot {
                  bytes32 value;
              }
              struct Uint256Slot {
                  uint256 value;
              }
              /**
               * @dev Returns an `AddressSlot` with member `value` located at `slot`.
               */
              function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
               */
              function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
               */
              function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
               */
              function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                  assembly {
                      r.slot := slot
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          import "../utils/Context.sol";
          /**
           * @dev Contract module which provides a basic access control mechanism, where
           * there is an account (an owner) that can be granted exclusive access to
           * specific functions.
           *
           * By default, the owner account will be the one that deploys the contract. This
           * can later be changed with {transferOwnership}.
           *
           * This module is used through inheritance. It will make available the modifier
           * `onlyOwner`, which can be applied to your functions to restrict their use to
           * the owner.
           */
          abstract contract Ownable is Context {
              address private _owner;
              event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
              /**
               * @dev Initializes the contract setting the deployer as the initial owner.
               */
              constructor () {
                  address msgSender = _msgSender();
                  _owner = msgSender;
                  emit OwnershipTransferred(address(0), msgSender);
              }
              /**
               * @dev Returns the address of the current owner.
               */
              function owner() public view virtual returns (address) {
                  return _owner;
              }
              /**
               * @dev Throws if called by any account other than the owner.
               */
              modifier onlyOwner() {
                  require(owner() == _msgSender(), "Ownable: caller is not the owner");
                  _;
              }
              /**
               * @dev Leaves the contract without owner. It will not be possible to call
               * `onlyOwner` functions anymore. Can only be called by the current owner.
               *
               * NOTE: Renouncing ownership will leave the contract without an owner,
               * thereby removing any functionality that is only available to the owner.
               */
              function renounceOwnership() public virtual onlyOwner {
                  emit OwnershipTransferred(_owner, address(0));
                  _owner = address(0);
              }
              /**
               * @dev Transfers ownership of the contract to a new account (`newOwner`).
               * Can only be called by the current owner.
               */
              function transferOwnership(address newOwner) public virtual onlyOwner {
                  require(newOwner != address(0), "Ownable: new owner is the zero address");
                  emit OwnershipTransferred(_owner, newOwner);
                  _owner = newOwner;
              }
          }
          // SPDX-License-Identifier: MIT
          pragma solidity ^0.8.0;
          /*
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract Context {
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
                  return msg.data;
              }
          }
          

          File 4 of 6: GnosisSafe
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          import "./base/ModuleManager.sol";
          import "./base/OwnerManager.sol";
          import "./base/FallbackManager.sol";
          import "./base/GuardManager.sol";
          import "./common/EtherPaymentFallback.sol";
          import "./common/Singleton.sol";
          import "./common/SignatureDecoder.sol";
          import "./common/SecuredTokenTransfer.sol";
          import "./common/StorageAccessible.sol";
          import "./interfaces/ISignatureValidator.sol";
          import "./external/GnosisSafeMath.sol";
          /// @title Gnosis Safe - A multisignature wallet with support for confirmations using signed messages based on ERC191.
          /// @author Stefan George - <[email protected]>
          /// @author Richard Meissner - <[email protected]>
          contract GnosisSafe is
              EtherPaymentFallback,
              Singleton,
              ModuleManager,
              OwnerManager,
              SignatureDecoder,
              SecuredTokenTransfer,
              ISignatureValidatorConstants,
              FallbackManager,
              StorageAccessible,
              GuardManager
          {
              using GnosisSafeMath for uint256;
              string public constant VERSION = "1.3.0";
              // keccak256(
              //     "EIP712Domain(uint256 chainId,address verifyingContract)"
              // );
              bytes32 private constant DOMAIN_SEPARATOR_TYPEHASH = 0x47e79534a245952e8b16893a336b85a3d9ea9fa8c573f3d803afb92a79469218;
              // keccak256(
              //     "SafeTx(address to,uint256 value,bytes data,uint8 operation,uint256 safeTxGas,uint256 baseGas,uint256 gasPrice,address gasToken,address refundReceiver,uint256 nonce)"
              // );
              bytes32 private constant SAFE_TX_TYPEHASH = 0xbb8310d486368db6bd6f849402fdd73ad53d316b5a4b2644ad6efe0f941286d8;
              event SafeSetup(address indexed initiator, address[] owners, uint256 threshold, address initializer, address fallbackHandler);
              event ApproveHash(bytes32 indexed approvedHash, address indexed owner);
              event SignMsg(bytes32 indexed msgHash);
              event ExecutionFailure(bytes32 txHash, uint256 payment);
              event ExecutionSuccess(bytes32 txHash, uint256 payment);
              uint256 public nonce;
              bytes32 private _deprecatedDomainSeparator;
              // Mapping to keep track of all message hashes that have been approve by ALL REQUIRED owners
              mapping(bytes32 => uint256) public signedMessages;
              // Mapping to keep track of all hashes (message or transaction) that have been approve by ANY owners
              mapping(address => mapping(bytes32 => uint256)) public approvedHashes;
              // This constructor ensures that this contract can only be used as a master copy for Proxy contracts
              constructor() {
                  // By setting the threshold it is not possible to call setup anymore,
                  // so we create a Safe with 0 owners and threshold 1.
                  // This is an unusable Safe, perfect for the singleton
                  threshold = 1;
              }
              /// @dev Setup function sets initial storage of contract.
              /// @param _owners List of Safe owners.
              /// @param _threshold Number of required confirmations for a Safe transaction.
              /// @param to Contract address for optional delegate call.
              /// @param data Data payload for optional delegate call.
              /// @param fallbackHandler Handler for fallback calls to this contract
              /// @param paymentToken Token that should be used for the payment (0 is ETH)
              /// @param payment Value that should be paid
              /// @param paymentReceiver Adddress that should receive the payment (or 0 if tx.origin)
              function setup(
                  address[] calldata _owners,
                  uint256 _threshold,
                  address to,
                  bytes calldata data,
                  address fallbackHandler,
                  address paymentToken,
                  uint256 payment,
                  address payable paymentReceiver
              ) external {
                  // setupOwners checks if the Threshold is already set, therefore preventing that this method is called twice
                  setupOwners(_owners, _threshold);
                  if (fallbackHandler != address(0)) internalSetFallbackHandler(fallbackHandler);
                  // As setupOwners can only be called if the contract has not been initialized we don't need a check for setupModules
                  setupModules(to, data);
                  if (payment > 0) {
                      // To avoid running into issues with EIP-170 we reuse the handlePayment function (to avoid adjusting code of that has been verified we do not adjust the method itself)
                      // baseGas = 0, gasPrice = 1 and gas = payment => amount = (payment + 0) * 1 = payment
                      handlePayment(payment, 0, 1, paymentToken, paymentReceiver);
                  }
                  emit SafeSetup(msg.sender, _owners, _threshold, to, fallbackHandler);
              }
              /// @dev Allows to execute a Safe transaction confirmed by required number of owners and then pays the account that submitted the transaction.
              ///      Note: The fees are always transferred, even if the user transaction fails.
              /// @param to Destination address of Safe transaction.
              /// @param value Ether value of Safe transaction.
              /// @param data Data payload of Safe transaction.
              /// @param operation Operation type of Safe transaction.
              /// @param safeTxGas Gas that should be used for the Safe transaction.
              /// @param baseGas Gas costs that are independent of the transaction execution(e.g. base transaction fee, signature check, payment of the refund)
              /// @param gasPrice Gas price that should be used for the payment calculation.
              /// @param gasToken Token address (or 0 if ETH) that is used for the payment.
              /// @param refundReceiver Address of receiver of gas payment (or 0 if tx.origin).
              /// @param signatures Packed signature data ({bytes32 r}{bytes32 s}{uint8 v})
              function execTransaction(
                  address to,
                  uint256 value,
                  bytes calldata data,
                  Enum.Operation operation,
                  uint256 safeTxGas,
                  uint256 baseGas,
                  uint256 gasPrice,
                  address gasToken,
                  address payable refundReceiver,
                  bytes memory signatures
              ) public payable virtual returns (bool success) {
                  bytes32 txHash;
                  // Use scope here to limit variable lifetime and prevent `stack too deep` errors
                  {
                      bytes memory txHashData =
                          encodeTransactionData(
                              // Transaction info
                              to,
                              value,
                              data,
                              operation,
                              safeTxGas,
                              // Payment info
                              baseGas,
                              gasPrice,
                              gasToken,
                              refundReceiver,
                              // Signature info
                              nonce
                          );
                      // Increase nonce and execute transaction.
                      nonce++;
                      txHash = keccak256(txHashData);
                      checkSignatures(txHash, txHashData, signatures);
                  }
                  address guard = getGuard();
                  {
                      if (guard != address(0)) {
                          Guard(guard).checkTransaction(
                              // Transaction info
                              to,
                              value,
                              data,
                              operation,
                              safeTxGas,
                              // Payment info
                              baseGas,
                              gasPrice,
                              gasToken,
                              refundReceiver,
                              // Signature info
                              signatures,
                              msg.sender
                          );
                      }
                  }
                  // We require some gas to emit the events (at least 2500) after the execution and some to perform code until the execution (500)
                  // We also include the 1/64 in the check that is not send along with a call to counteract potential shortings because of EIP-150
                  require(gasleft() >= ((safeTxGas * 64) / 63).max(safeTxGas + 2500) + 500, "GS010");
                  // Use scope here to limit variable lifetime and prevent `stack too deep` errors
                  {
                      uint256 gasUsed = gasleft();
                      // If the gasPrice is 0 we assume that nearly all available gas can be used (it is always more than safeTxGas)
                      // We only substract 2500 (compared to the 3000 before) to ensure that the amount passed is still higher than safeTxGas
                      success = execute(to, value, data, operation, gasPrice == 0 ? (gasleft() - 2500) : safeTxGas);
                      gasUsed = gasUsed.sub(gasleft());
                      // If no safeTxGas and no gasPrice was set (e.g. both are 0), then the internal tx is required to be successful
                      // This makes it possible to use `estimateGas` without issues, as it searches for the minimum gas where the tx doesn't revert
                      require(success || safeTxGas != 0 || gasPrice != 0, "GS013");
                      // We transfer the calculated tx costs to the tx.origin to avoid sending it to intermediate contracts that have made calls
                      uint256 payment = 0;
                      if (gasPrice > 0) {
                          payment = handlePayment(gasUsed, baseGas, gasPrice, gasToken, refundReceiver);
                      }
                      if (success) emit ExecutionSuccess(txHash, payment);
                      else emit ExecutionFailure(txHash, payment);
                  }
                  {
                      if (guard != address(0)) {
                          Guard(guard).checkAfterExecution(txHash, success);
                      }
                  }
              }
              function handlePayment(
                  uint256 gasUsed,
                  uint256 baseGas,
                  uint256 gasPrice,
                  address gasToken,
                  address payable refundReceiver
              ) private returns (uint256 payment) {
                  // solhint-disable-next-line avoid-tx-origin
                  address payable receiver = refundReceiver == address(0) ? payable(tx.origin) : refundReceiver;
                  if (gasToken == address(0)) {
                      // For ETH we will only adjust the gas price to not be higher than the actual used gas price
                      payment = gasUsed.add(baseGas).mul(gasPrice < tx.gasprice ? gasPrice : tx.gasprice);
                      require(receiver.send(payment), "GS011");
                  } else {
                      payment = gasUsed.add(baseGas).mul(gasPrice);
                      require(transferToken(gasToken, receiver, payment), "GS012");
                  }
              }
              /**
               * @dev Checks whether the signature provided is valid for the provided data, hash. Will revert otherwise.
               * @param dataHash Hash of the data (could be either a message hash or transaction hash)
               * @param data That should be signed (this is passed to an external validator contract)
               * @param signatures Signature data that should be verified. Can be ECDSA signature, contract signature (EIP-1271) or approved hash.
               */
              function checkSignatures(
                  bytes32 dataHash,
                  bytes memory data,
                  bytes memory signatures
              ) public view {
                  // Load threshold to avoid multiple storage loads
                  uint256 _threshold = threshold;
                  // Check that a threshold is set
                  require(_threshold > 0, "GS001");
                  checkNSignatures(dataHash, data, signatures, _threshold);
              }
              /**
               * @dev Checks whether the signature provided is valid for the provided data, hash. Will revert otherwise.
               * @param dataHash Hash of the data (could be either a message hash or transaction hash)
               * @param data That should be signed (this is passed to an external validator contract)
               * @param signatures Signature data that should be verified. Can be ECDSA signature, contract signature (EIP-1271) or approved hash.
               * @param requiredSignatures Amount of required valid signatures.
               */
              function checkNSignatures(
                  bytes32 dataHash,
                  bytes memory data,
                  bytes memory signatures,
                  uint256 requiredSignatures
              ) public view {
                  // Check that the provided signature data is not too short
                  require(signatures.length >= requiredSignatures.mul(65), "GS020");
                  // There cannot be an owner with address 0.
                  address lastOwner = address(0);
                  address currentOwner;
                  uint8 v;
                  bytes32 r;
                  bytes32 s;
                  uint256 i;
                  for (i = 0; i < requiredSignatures; i++) {
                      (v, r, s) = signatureSplit(signatures, i);
                      if (v == 0) {
                          // If v is 0 then it is a contract signature
                          // When handling contract signatures the address of the contract is encoded into r
                          currentOwner = address(uint160(uint256(r)));
                          // Check that signature data pointer (s) is not pointing inside the static part of the signatures bytes
                          // This check is not completely accurate, since it is possible that more signatures than the threshold are send.
                          // Here we only check that the pointer is not pointing inside the part that is being processed
                          require(uint256(s) >= requiredSignatures.mul(65), "GS021");
                          // Check that signature data pointer (s) is in bounds (points to the length of data -> 32 bytes)
                          require(uint256(s).add(32) <= signatures.length, "GS022");
                          // Check if the contract signature is in bounds: start of data is s + 32 and end is start + signature length
                          uint256 contractSignatureLen;
                          // solhint-disable-next-line no-inline-assembly
                          assembly {
                              contractSignatureLen := mload(add(add(signatures, s), 0x20))
                          }
                          require(uint256(s).add(32).add(contractSignatureLen) <= signatures.length, "GS023");
                          // Check signature
                          bytes memory contractSignature;
                          // solhint-disable-next-line no-inline-assembly
                          assembly {
                              // The signature data for contract signatures is appended to the concatenated signatures and the offset is stored in s
                              contractSignature := add(add(signatures, s), 0x20)
                          }
                          require(ISignatureValidator(currentOwner).isValidSignature(data, contractSignature) == EIP1271_MAGIC_VALUE, "GS024");
                      } else if (v == 1) {
                          // If v is 1 then it is an approved hash
                          // When handling approved hashes the address of the approver is encoded into r
                          currentOwner = address(uint160(uint256(r)));
                          // Hashes are automatically approved by the sender of the message or when they have been pre-approved via a separate transaction
                          require(msg.sender == currentOwner || approvedHashes[currentOwner][dataHash] != 0, "GS025");
                      } else if (v > 30) {
                          // If v > 30 then default va (27,28) has been adjusted for eth_sign flow
                          // To support eth_sign and similar we adjust v and hash the messageHash with the Ethereum message prefix before applying ecrecover
                          currentOwner = ecrecover(keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
          32", dataHash)), v - 4, r, s);
                      } else {
                          // Default is the ecrecover flow with the provided data hash
                          // Use ecrecover with the messageHash for EOA signatures
                          currentOwner = ecrecover(dataHash, v, r, s);
                      }
                      require(currentOwner > lastOwner && owners[currentOwner] != address(0) && currentOwner != SENTINEL_OWNERS, "GS026");
                      lastOwner = currentOwner;
                  }
              }
              /// @dev Allows to estimate a Safe transaction.
              ///      This method is only meant for estimation purpose, therefore the call will always revert and encode the result in the revert data.
              ///      Since the `estimateGas` function includes refunds, call this method to get an estimated of the costs that are deducted from the safe with `execTransaction`
              /// @param to Destination address of Safe transaction.
              /// @param value Ether value of Safe transaction.
              /// @param data Data payload of Safe transaction.
              /// @param operation Operation type of Safe transaction.
              /// @return Estimate without refunds and overhead fees (base transaction and payload data gas costs).
              /// @notice Deprecated in favor of common/StorageAccessible.sol and will be removed in next version.
              function requiredTxGas(
                  address to,
                  uint256 value,
                  bytes calldata data,
                  Enum.Operation operation
              ) external returns (uint256) {
                  uint256 startGas = gasleft();
                  // We don't provide an error message here, as we use it to return the estimate
                  require(execute(to, value, data, operation, gasleft()));
                  uint256 requiredGas = startGas - gasleft();
                  // Convert response to string and return via error message
                  revert(string(abi.encodePacked(requiredGas)));
              }
              /**
               * @dev Marks a hash as approved. This can be used to validate a hash that is used by a signature.
               * @param hashToApprove The hash that should be marked as approved for signatures that are verified by this contract.
               */
              function approveHash(bytes32 hashToApprove) external {
                  require(owners[msg.sender] != address(0), "GS030");
                  approvedHashes[msg.sender][hashToApprove] = 1;
                  emit ApproveHash(hashToApprove, msg.sender);
              }
              /// @dev Returns the chain id used by this contract.
              function getChainId() public view returns (uint256) {
                  uint256 id;
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      id := chainid()
                  }
                  return id;
              }
              function domainSeparator() public view returns (bytes32) {
                  return keccak256(abi.encode(DOMAIN_SEPARATOR_TYPEHASH, getChainId(), this));
              }
              /// @dev Returns the bytes that are hashed to be signed by owners.
              /// @param to Destination address.
              /// @param value Ether value.
              /// @param data Data payload.
              /// @param operation Operation type.
              /// @param safeTxGas Gas that should be used for the safe transaction.
              /// @param baseGas Gas costs for that are independent of the transaction execution(e.g. base transaction fee, signature check, payment of the refund)
              /// @param gasPrice Maximum gas price that should be used for this transaction.
              /// @param gasToken Token address (or 0 if ETH) that is used for the payment.
              /// @param refundReceiver Address of receiver of gas payment (or 0 if tx.origin).
              /// @param _nonce Transaction nonce.
              /// @return Transaction hash bytes.
              function encodeTransactionData(
                  address to,
                  uint256 value,
                  bytes calldata data,
                  Enum.Operation operation,
                  uint256 safeTxGas,
                  uint256 baseGas,
                  uint256 gasPrice,
                  address gasToken,
                  address refundReceiver,
                  uint256 _nonce
              ) public view returns (bytes memory) {
                  bytes32 safeTxHash =
                      keccak256(
                          abi.encode(
                              SAFE_TX_TYPEHASH,
                              to,
                              value,
                              keccak256(data),
                              operation,
                              safeTxGas,
                              baseGas,
                              gasPrice,
                              gasToken,
                              refundReceiver,
                              _nonce
                          )
                      );
                  return abi.encodePacked(bytes1(0x19), bytes1(0x01), domainSeparator(), safeTxHash);
              }
              /// @dev Returns hash to be signed by owners.
              /// @param to Destination address.
              /// @param value Ether value.
              /// @param data Data payload.
              /// @param operation Operation type.
              /// @param safeTxGas Fas that should be used for the safe transaction.
              /// @param baseGas Gas costs for data used to trigger the safe transaction.
              /// @param gasPrice Maximum gas price that should be used for this transaction.
              /// @param gasToken Token address (or 0 if ETH) that is used for the payment.
              /// @param refundReceiver Address of receiver of gas payment (or 0 if tx.origin).
              /// @param _nonce Transaction nonce.
              /// @return Transaction hash.
              function getTransactionHash(
                  address to,
                  uint256 value,
                  bytes calldata data,
                  Enum.Operation operation,
                  uint256 safeTxGas,
                  uint256 baseGas,
                  uint256 gasPrice,
                  address gasToken,
                  address refundReceiver,
                  uint256 _nonce
              ) public view returns (bytes32) {
                  return keccak256(encodeTransactionData(to, value, data, operation, safeTxGas, baseGas, gasPrice, gasToken, refundReceiver, _nonce));
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          import "../common/Enum.sol";
          /// @title Executor - A contract that can execute transactions
          /// @author Richard Meissner - <[email protected]>
          contract Executor {
              function execute(
                  address to,
                  uint256 value,
                  bytes memory data,
                  Enum.Operation operation,
                  uint256 txGas
              ) internal returns (bool success) {
                  if (operation == Enum.Operation.DelegateCall) {
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          success := delegatecall(txGas, to, add(data, 0x20), mload(data), 0, 0)
                      }
                  } else {
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          success := call(txGas, to, value, add(data, 0x20), mload(data), 0, 0)
                      }
                  }
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          import "../common/SelfAuthorized.sol";
          /// @title Fallback Manager - A contract that manages fallback calls made to this contract
          /// @author Richard Meissner - <[email protected]>
          contract FallbackManager is SelfAuthorized {
              event ChangedFallbackHandler(address handler);
              // keccak256("fallback_manager.handler.address")
              bytes32 internal constant FALLBACK_HANDLER_STORAGE_SLOT = 0x6c9a6c4a39284e37ed1cf53d337577d14212a4870fb976a4366c693b939918d5;
              function internalSetFallbackHandler(address handler) internal {
                  bytes32 slot = FALLBACK_HANDLER_STORAGE_SLOT;
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      sstore(slot, handler)
                  }
              }
              /// @dev Allows to add a contract to handle fallback calls.
              ///      Only fallback calls without value and with data will be forwarded.
              ///      This can only be done via a Safe transaction.
              /// @param handler contract to handle fallbacks calls.
              function setFallbackHandler(address handler) public authorized {
                  internalSetFallbackHandler(handler);
                  emit ChangedFallbackHandler(handler);
              }
              // solhint-disable-next-line payable-fallback,no-complex-fallback
              fallback() external {
                  bytes32 slot = FALLBACK_HANDLER_STORAGE_SLOT;
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      let handler := sload(slot)
                      if iszero(handler) {
                          return(0, 0)
                      }
                      calldatacopy(0, 0, calldatasize())
                      // The msg.sender address is shifted to the left by 12 bytes to remove the padding
                      // Then the address without padding is stored right after the calldata
                      mstore(calldatasize(), shl(96, caller()))
                      // Add 20 bytes for the address appended add the end
                      let success := call(gas(), handler, 0, 0, add(calldatasize(), 20), 0, 0)
                      returndatacopy(0, 0, returndatasize())
                      if iszero(success) {
                          revert(0, returndatasize())
                      }
                      return(0, returndatasize())
                  }
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          import "../common/Enum.sol";
          import "../common/SelfAuthorized.sol";
          interface Guard {
              function checkTransaction(
                  address to,
                  uint256 value,
                  bytes memory data,
                  Enum.Operation operation,
                  uint256 safeTxGas,
                  uint256 baseGas,
                  uint256 gasPrice,
                  address gasToken,
                  address payable refundReceiver,
                  bytes memory signatures,
                  address msgSender
              ) external;
              function checkAfterExecution(bytes32 txHash, bool success) external;
          }
          /// @title Fallback Manager - A contract that manages fallback calls made to this contract
          /// @author Richard Meissner - <[email protected]>
          contract GuardManager is SelfAuthorized {
              event ChangedGuard(address guard);
              // keccak256("guard_manager.guard.address")
              bytes32 internal constant GUARD_STORAGE_SLOT = 0x4a204f620c8c5ccdca3fd54d003badd85ba500436a431f0cbda4f558c93c34c8;
              /// @dev Set a guard that checks transactions before execution
              /// @param guard The address of the guard to be used or the 0 address to disable the guard
              function setGuard(address guard) external authorized {
                  bytes32 slot = GUARD_STORAGE_SLOT;
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      sstore(slot, guard)
                  }
                  emit ChangedGuard(guard);
              }
              function getGuard() internal view returns (address guard) {
                  bytes32 slot = GUARD_STORAGE_SLOT;
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      guard := sload(slot)
                  }
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          import "../common/Enum.sol";
          import "../common/SelfAuthorized.sol";
          import "./Executor.sol";
          /// @title Module Manager - A contract that manages modules that can execute transactions via this contract
          /// @author Stefan George - <[email protected]>
          /// @author Richard Meissner - <[email protected]>
          contract ModuleManager is SelfAuthorized, Executor {
              event EnabledModule(address module);
              event DisabledModule(address module);
              event ExecutionFromModuleSuccess(address indexed module);
              event ExecutionFromModuleFailure(address indexed module);
              address internal constant SENTINEL_MODULES = address(0x1);
              mapping(address => address) internal modules;
              function setupModules(address to, bytes memory data) internal {
                  require(modules[SENTINEL_MODULES] == address(0), "GS100");
                  modules[SENTINEL_MODULES] = SENTINEL_MODULES;
                  if (to != address(0))
                      // Setup has to complete successfully or transaction fails.
                      require(execute(to, 0, data, Enum.Operation.DelegateCall, gasleft()), "GS000");
              }
              /// @dev Allows to add a module to the whitelist.
              ///      This can only be done via a Safe transaction.
              /// @notice Enables the module `module` for the Safe.
              /// @param module Module to be whitelisted.
              function enableModule(address module) public authorized {
                  // Module address cannot be null or sentinel.
                  require(module != address(0) && module != SENTINEL_MODULES, "GS101");
                  // Module cannot be added twice.
                  require(modules[module] == address(0), "GS102");
                  modules[module] = modules[SENTINEL_MODULES];
                  modules[SENTINEL_MODULES] = module;
                  emit EnabledModule(module);
              }
              /// @dev Allows to remove a module from the whitelist.
              ///      This can only be done via a Safe transaction.
              /// @notice Disables the module `module` for the Safe.
              /// @param prevModule Module that pointed to the module to be removed in the linked list
              /// @param module Module to be removed.
              function disableModule(address prevModule, address module) public authorized {
                  // Validate module address and check that it corresponds to module index.
                  require(module != address(0) && module != SENTINEL_MODULES, "GS101");
                  require(modules[prevModule] == module, "GS103");
                  modules[prevModule] = modules[module];
                  modules[module] = address(0);
                  emit DisabledModule(module);
              }
              /// @dev Allows a Module to execute a Safe transaction without any further confirmations.
              /// @param to Destination address of module transaction.
              /// @param value Ether value of module transaction.
              /// @param data Data payload of module transaction.
              /// @param operation Operation type of module transaction.
              function execTransactionFromModule(
                  address to,
                  uint256 value,
                  bytes memory data,
                  Enum.Operation operation
              ) public virtual returns (bool success) {
                  // Only whitelisted modules are allowed.
                  require(msg.sender != SENTINEL_MODULES && modules[msg.sender] != address(0), "GS104");
                  // Execute transaction without further confirmations.
                  success = execute(to, value, data, operation, gasleft());
                  if (success) emit ExecutionFromModuleSuccess(msg.sender);
                  else emit ExecutionFromModuleFailure(msg.sender);
              }
              /// @dev Allows a Module to execute a Safe transaction without any further confirmations and return data
              /// @param to Destination address of module transaction.
              /// @param value Ether value of module transaction.
              /// @param data Data payload of module transaction.
              /// @param operation Operation type of module transaction.
              function execTransactionFromModuleReturnData(
                  address to,
                  uint256 value,
                  bytes memory data,
                  Enum.Operation operation
              ) public returns (bool success, bytes memory returnData) {
                  success = execTransactionFromModule(to, value, data, operation);
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      // Load free memory location
                      let ptr := mload(0x40)
                      // We allocate memory for the return data by setting the free memory location to
                      // current free memory location + data size + 32 bytes for data size value
                      mstore(0x40, add(ptr, add(returndatasize(), 0x20)))
                      // Store the size
                      mstore(ptr, returndatasize())
                      // Store the data
                      returndatacopy(add(ptr, 0x20), 0, returndatasize())
                      // Point the return data to the correct memory location
                      returnData := ptr
                  }
              }
              /// @dev Returns if an module is enabled
              /// @return True if the module is enabled
              function isModuleEnabled(address module) public view returns (bool) {
                  return SENTINEL_MODULES != module && modules[module] != address(0);
              }
              /// @dev Returns array of modules.
              /// @param start Start of the page.
              /// @param pageSize Maximum number of modules that should be returned.
              /// @return array Array of modules.
              /// @return next Start of the next page.
              function getModulesPaginated(address start, uint256 pageSize) external view returns (address[] memory array, address next) {
                  // Init array with max page size
                  array = new address[](pageSize);
                  // Populate return array
                  uint256 moduleCount = 0;
                  address currentModule = modules[start];
                  while (currentModule != address(0x0) && currentModule != SENTINEL_MODULES && moduleCount < pageSize) {
                      array[moduleCount] = currentModule;
                      currentModule = modules[currentModule];
                      moduleCount++;
                  }
                  next = currentModule;
                  // Set correct size of returned array
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      mstore(array, moduleCount)
                  }
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          import "../common/SelfAuthorized.sol";
          /// @title OwnerManager - Manages a set of owners and a threshold to perform actions.
          /// @author Stefan George - <[email protected]>
          /// @author Richard Meissner - <[email protected]>
          contract OwnerManager is SelfAuthorized {
              event AddedOwner(address owner);
              event RemovedOwner(address owner);
              event ChangedThreshold(uint256 threshold);
              address internal constant SENTINEL_OWNERS = address(0x1);
              mapping(address => address) internal owners;
              uint256 internal ownerCount;
              uint256 internal threshold;
              /// @dev Setup function sets initial storage of contract.
              /// @param _owners List of Safe owners.
              /// @param _threshold Number of required confirmations for a Safe transaction.
              function setupOwners(address[] memory _owners, uint256 _threshold) internal {
                  // Threshold can only be 0 at initialization.
                  // Check ensures that setup function can only be called once.
                  require(threshold == 0, "GS200");
                  // Validate that threshold is smaller than number of added owners.
                  require(_threshold <= _owners.length, "GS201");
                  // There has to be at least one Safe owner.
                  require(_threshold >= 1, "GS202");
                  // Initializing Safe owners.
                  address currentOwner = SENTINEL_OWNERS;
                  for (uint256 i = 0; i < _owners.length; i++) {
                      // Owner address cannot be null.
                      address owner = _owners[i];
                      require(owner != address(0) && owner != SENTINEL_OWNERS && owner != address(this) && currentOwner != owner, "GS203");
                      // No duplicate owners allowed.
                      require(owners[owner] == address(0), "GS204");
                      owners[currentOwner] = owner;
                      currentOwner = owner;
                  }
                  owners[currentOwner] = SENTINEL_OWNERS;
                  ownerCount = _owners.length;
                  threshold = _threshold;
              }
              /// @dev Allows to add a new owner to the Safe and update the threshold at the same time.
              ///      This can only be done via a Safe transaction.
              /// @notice Adds the owner `owner` to the Safe and updates the threshold to `_threshold`.
              /// @param owner New owner address.
              /// @param _threshold New threshold.
              function addOwnerWithThreshold(address owner, uint256 _threshold) public authorized {
                  // Owner address cannot be null, the sentinel or the Safe itself.
                  require(owner != address(0) && owner != SENTINEL_OWNERS && owner != address(this), "GS203");
                  // No duplicate owners allowed.
                  require(owners[owner] == address(0), "GS204");
                  owners[owner] = owners[SENTINEL_OWNERS];
                  owners[SENTINEL_OWNERS] = owner;
                  ownerCount++;
                  emit AddedOwner(owner);
                  // Change threshold if threshold was changed.
                  if (threshold != _threshold) changeThreshold(_threshold);
              }
              /// @dev Allows to remove an owner from the Safe and update the threshold at the same time.
              ///      This can only be done via a Safe transaction.
              /// @notice Removes the owner `owner` from the Safe and updates the threshold to `_threshold`.
              /// @param prevOwner Owner that pointed to the owner to be removed in the linked list
              /// @param owner Owner address to be removed.
              /// @param _threshold New threshold.
              function removeOwner(
                  address prevOwner,
                  address owner,
                  uint256 _threshold
              ) public authorized {
                  // Only allow to remove an owner, if threshold can still be reached.
                  require(ownerCount - 1 >= _threshold, "GS201");
                  // Validate owner address and check that it corresponds to owner index.
                  require(owner != address(0) && owner != SENTINEL_OWNERS, "GS203");
                  require(owners[prevOwner] == owner, "GS205");
                  owners[prevOwner] = owners[owner];
                  owners[owner] = address(0);
                  ownerCount--;
                  emit RemovedOwner(owner);
                  // Change threshold if threshold was changed.
                  if (threshold != _threshold) changeThreshold(_threshold);
              }
              /// @dev Allows to swap/replace an owner from the Safe with another address.
              ///      This can only be done via a Safe transaction.
              /// @notice Replaces the owner `oldOwner` in the Safe with `newOwner`.
              /// @param prevOwner Owner that pointed to the owner to be replaced in the linked list
              /// @param oldOwner Owner address to be replaced.
              /// @param newOwner New owner address.
              function swapOwner(
                  address prevOwner,
                  address oldOwner,
                  address newOwner
              ) public authorized {
                  // Owner address cannot be null, the sentinel or the Safe itself.
                  require(newOwner != address(0) && newOwner != SENTINEL_OWNERS && newOwner != address(this), "GS203");
                  // No duplicate owners allowed.
                  require(owners[newOwner] == address(0), "GS204");
                  // Validate oldOwner address and check that it corresponds to owner index.
                  require(oldOwner != address(0) && oldOwner != SENTINEL_OWNERS, "GS203");
                  require(owners[prevOwner] == oldOwner, "GS205");
                  owners[newOwner] = owners[oldOwner];
                  owners[prevOwner] = newOwner;
                  owners[oldOwner] = address(0);
                  emit RemovedOwner(oldOwner);
                  emit AddedOwner(newOwner);
              }
              /// @dev Allows to update the number of required confirmations by Safe owners.
              ///      This can only be done via a Safe transaction.
              /// @notice Changes the threshold of the Safe to `_threshold`.
              /// @param _threshold New threshold.
              function changeThreshold(uint256 _threshold) public authorized {
                  // Validate that threshold is smaller than number of owners.
                  require(_threshold <= ownerCount, "GS201");
                  // There has to be at least one Safe owner.
                  require(_threshold >= 1, "GS202");
                  threshold = _threshold;
                  emit ChangedThreshold(threshold);
              }
              function getThreshold() public view returns (uint256) {
                  return threshold;
              }
              function isOwner(address owner) public view returns (bool) {
                  return owner != SENTINEL_OWNERS && owners[owner] != address(0);
              }
              /// @dev Returns array of owners.
              /// @return Array of Safe owners.
              function getOwners() public view returns (address[] memory) {
                  address[] memory array = new address[](ownerCount);
                  // populate return array
                  uint256 index = 0;
                  address currentOwner = owners[SENTINEL_OWNERS];
                  while (currentOwner != SENTINEL_OWNERS) {
                      array[index] = currentOwner;
                      currentOwner = owners[currentOwner];
                      index++;
                  }
                  return array;
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /// @title Enum - Collection of enums
          /// @author Richard Meissner - <[email protected]>
          contract Enum {
              enum Operation {Call, DelegateCall}
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /// @title EtherPaymentFallback - A contract that has a fallback to accept ether payments
          /// @author Richard Meissner - <[email protected]>
          contract EtherPaymentFallback {
              event SafeReceived(address indexed sender, uint256 value);
              /// @dev Fallback function accepts Ether transactions.
              receive() external payable {
                  emit SafeReceived(msg.sender, msg.value);
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /// @title SecuredTokenTransfer - Secure token transfer
          /// @author Richard Meissner - <[email protected]>
          contract SecuredTokenTransfer {
              /// @dev Transfers a token and returns if it was a success
              /// @param token Token that should be transferred
              /// @param receiver Receiver to whom the token should be transferred
              /// @param amount The amount of tokens that should be transferred
              function transferToken(
                  address token,
                  address receiver,
                  uint256 amount
              ) internal returns (bool transferred) {
                  // 0xa9059cbb - keccack("transfer(address,uint256)")
                  bytes memory data = abi.encodeWithSelector(0xa9059cbb, receiver, amount);
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      // We write the return value to scratch space.
                      // See https://docs.soliditylang.org/en/v0.7.6/internals/layout_in_memory.html#layout-in-memory
                      let success := call(sub(gas(), 10000), token, 0, add(data, 0x20), mload(data), 0, 0x20)
                      switch returndatasize()
                          case 0 {
                              transferred := success
                          }
                          case 0x20 {
                              transferred := iszero(or(iszero(success), iszero(mload(0))))
                          }
                          default {
                              transferred := 0
                          }
                  }
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /// @title SelfAuthorized - authorizes current contract to perform actions
          /// @author Richard Meissner - <[email protected]>
          contract SelfAuthorized {
              function requireSelfCall() private view {
                  require(msg.sender == address(this), "GS031");
              }
              modifier authorized() {
                  // This is a function call as it minimized the bytecode size
                  requireSelfCall();
                  _;
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /// @title SignatureDecoder - Decodes signatures that a encoded as bytes
          /// @author Richard Meissner - <[email protected]>
          contract SignatureDecoder {
              /// @dev divides bytes signature into `uint8 v, bytes32 r, bytes32 s`.
              /// @notice Make sure to peform a bounds check for @param pos, to avoid out of bounds access on @param signatures
              /// @param pos which signature to read. A prior bounds check of this parameter should be performed, to avoid out of bounds access
              /// @param signatures concatenated rsv signatures
              function signatureSplit(bytes memory signatures, uint256 pos)
                  internal
                  pure
                  returns (
                      uint8 v,
                      bytes32 r,
                      bytes32 s
                  )
              {
                  // The signature format is a compact form of:
                  //   {bytes32 r}{bytes32 s}{uint8 v}
                  // Compact means, uint8 is not padded to 32 bytes.
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      let signaturePos := mul(0x41, pos)
                      r := mload(add(signatures, add(signaturePos, 0x20)))
                      s := mload(add(signatures, add(signaturePos, 0x40)))
                      // Here we are loading the last 32 bytes, including 31 bytes
                      // of 's'. There is no 'mload8' to do this.
                      //
                      // 'byte' is not working due to the Solidity parser, so lets
                      // use the second best option, 'and'
                      v := and(mload(add(signatures, add(signaturePos, 0x41))), 0xff)
                  }
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /// @title Singleton - Base for singleton contracts (should always be first super contract)
          ///         This contract is tightly coupled to our proxy contract (see `proxies/GnosisSafeProxy.sol`)
          /// @author Richard Meissner - <[email protected]>
          contract Singleton {
              // singleton always needs to be first declared variable, to ensure that it is at the same location as in the Proxy contract.
              // It should also always be ensured that the address is stored alone (uses a full word)
              address private singleton;
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /// @title StorageAccessible - generic base contract that allows callers to access all internal storage.
          /// @notice See https://github.com/gnosis/util-contracts/blob/bb5fe5fb5df6d8400998094fb1b32a178a47c3a1/contracts/StorageAccessible.sol
          contract StorageAccessible {
              /**
               * @dev Reads `length` bytes of storage in the currents contract
               * @param offset - the offset in the current contract's storage in words to start reading from
               * @param length - the number of words (32 bytes) of data to read
               * @return the bytes that were read.
               */
              function getStorageAt(uint256 offset, uint256 length) public view returns (bytes memory) {
                  bytes memory result = new bytes(length * 32);
                  for (uint256 index = 0; index < length; index++) {
                      // solhint-disable-next-line no-inline-assembly
                      assembly {
                          let word := sload(add(offset, index))
                          mstore(add(add(result, 0x20), mul(index, 0x20)), word)
                      }
                  }
                  return result;
              }
              /**
               * @dev Performs a delegetecall on a targetContract in the context of self.
               * Internally reverts execution to avoid side effects (making it static).
               *
               * This method reverts with data equal to `abi.encode(bool(success), bytes(response))`.
               * Specifically, the `returndata` after a call to this method will be:
               * `success:bool || response.length:uint256 || response:bytes`.
               *
               * @param targetContract Address of the contract containing the code to execute.
               * @param calldataPayload Calldata that should be sent to the target contract (encoded method name and arguments).
               */
              function simulateAndRevert(address targetContract, bytes memory calldataPayload) external {
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      let success := delegatecall(gas(), targetContract, add(calldataPayload, 0x20), mload(calldataPayload), 0, 0)
                      mstore(0x00, success)
                      mstore(0x20, returndatasize())
                      returndatacopy(0x40, 0, returndatasize())
                      revert(0, add(returndatasize(), 0x40))
                  }
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /**
           * @title GnosisSafeMath
           * @dev Math operations with safety checks that revert on error
           * Renamed from SafeMath to GnosisSafeMath to avoid conflicts
           * TODO: remove once open zeppelin update to solc 0.5.0
           */
          library GnosisSafeMath {
              /**
               * @dev Multiplies two numbers, reverts on overflow.
               */
              function mul(uint256 a, uint256 b) internal pure returns (uint256) {
                  // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                  // benefit is lost if 'b' is also tested.
                  // See: https://github.com/OpenZeppelin/openzeppelin-solidity/pull/522
                  if (a == 0) {
                      return 0;
                  }
                  uint256 c = a * b;
                  require(c / a == b);
                  return c;
              }
              /**
               * @dev Subtracts two numbers, reverts on overflow (i.e. if subtrahend is greater than minuend).
               */
              function sub(uint256 a, uint256 b) internal pure returns (uint256) {
                  require(b <= a);
                  uint256 c = a - b;
                  return c;
              }
              /**
               * @dev Adds two numbers, reverts on overflow.
               */
              function add(uint256 a, uint256 b) internal pure returns (uint256) {
                  uint256 c = a + b;
                  require(c >= a);
                  return c;
              }
              /**
               * @dev Returns the largest of two numbers.
               */
              function max(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a >= b ? a : b;
              }
          }
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          contract ISignatureValidatorConstants {
              // bytes4(keccak256("isValidSignature(bytes,bytes)")
              bytes4 internal constant EIP1271_MAGIC_VALUE = 0x20c13b0b;
          }
          abstract contract ISignatureValidator is ISignatureValidatorConstants {
              /**
               * @dev Should return whether the signature provided is valid for the provided data
               * @param _data Arbitrary length data signed on the behalf of address(this)
               * @param _signature Signature byte array associated with _data
               *
               * MUST return the bytes4 magic value 0x20c13b0b when function passes.
               * MUST NOT modify state (using STATICCALL for solc < 0.5, view modifier for solc > 0.5)
               * MUST allow external calls
               */
              function isValidSignature(bytes memory _data, bytes memory _signature) public view virtual returns (bytes4);
          }
          

          File 5 of 6: MultiSendCallOnly
          // SPDX-License-Identifier: LGPL-3.0-only
          pragma solidity >=0.7.0 <0.9.0;
          /// @title Multi Send Call Only - Allows to batch multiple transactions into one, but only calls
          /// @author Stefan George - <[email protected]>
          /// @author Richard Meissner - <[email protected]>
          /// @notice The guard logic is not required here as this contract doesn't support nested delegate calls
          contract MultiSendCallOnly {
              /// @dev Sends multiple transactions and reverts all if one fails.
              /// @param transactions Encoded transactions. Each transaction is encoded as a packed bytes of
              ///                     operation has to be uint8(0) in this version (=> 1 byte),
              ///                     to as a address (=> 20 bytes),
              ///                     value as a uint256 (=> 32 bytes),
              ///                     data length as a uint256 (=> 32 bytes),
              ///                     data as bytes.
              ///                     see abi.encodePacked for more information on packed encoding
              /// @notice The code is for most part the same as the normal MultiSend (to keep compatibility),
              ///         but reverts if a transaction tries to use a delegatecall.
              /// @notice This method is payable as delegatecalls keep the msg.value from the previous call
              ///         If the calling method (e.g. execTransaction) received ETH this would revert otherwise
              function multiSend(bytes memory transactions) public payable {
                  // solhint-disable-next-line no-inline-assembly
                  assembly {
                      let length := mload(transactions)
                      let i := 0x20
                      for {
                          // Pre block is not used in "while mode"
                      } lt(i, length) {
                          // Post block is not used in "while mode"
                      } {
                          // First byte of the data is the operation.
                          // We shift by 248 bits (256 - 8 [operation byte]) it right since mload will always load 32 bytes (a word).
                          // This will also zero out unused data.
                          let operation := shr(0xf8, mload(add(transactions, i)))
                          // We offset the load address by 1 byte (operation byte)
                          // We shift it right by 96 bits (256 - 160 [20 address bytes]) to right-align the data and zero out unused data.
                          let to := shr(0x60, mload(add(transactions, add(i, 0x01))))
                          // We offset the load address by 21 byte (operation byte + 20 address bytes)
                          let value := mload(add(transactions, add(i, 0x15)))
                          // We offset the load address by 53 byte (operation byte + 20 address bytes + 32 value bytes)
                          let dataLength := mload(add(transactions, add(i, 0x35)))
                          // We offset the load address by 85 byte (operation byte + 20 address bytes + 32 value bytes + 32 data length bytes)
                          let data := add(transactions, add(i, 0x55))
                          let success := 0
                          switch operation
                              case 0 {
                                  success := call(gas(), to, value, data, dataLength, 0, 0)
                              }
                              // This version does not allow delegatecalls
                              case 1 {
                                  revert(0, 0)
                              }
                          if eq(success, 0) {
                              revert(0, 0)
                          }
                          // Next entry starts at 85 byte + data length
                          i := add(i, add(0x55, dataLength))
                      }
                  }
              }
          }
          

          File 6 of 6: Gala
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (access/AccessControl.sol)
          pragma solidity ^0.8.0;
          import "./IAccessControlUpgradeable.sol";
          import "../utils/ContextUpgradeable.sol";
          import "../utils/StringsUpgradeable.sol";
          import "../utils/introspection/ERC165Upgradeable.sol";
          import "../proxy/utils/Initializable.sol";
          /**
           * @dev Contract module that allows children to implement role-based access
           * control mechanisms. This is a lightweight version that doesn't allow enumerating role
           * members except through off-chain means by accessing the contract event logs. Some
           * applications may benefit from on-chain enumerability, for those cases see
           * {AccessControlEnumerable}.
           *
           * Roles are referred to by their `bytes32` identifier. These should be exposed
           * in the external API and be unique. The best way to achieve this is by
           * using `public constant` hash digests:
           *
           * ```
           * bytes32 public constant MY_ROLE = keccak256("MY_ROLE");
           * ```
           *
           * Roles can be used to represent a set of permissions. To restrict access to a
           * function call, use {hasRole}:
           *
           * ```
           * function foo() public {
           *     require(hasRole(MY_ROLE, msg.sender));
           *     ...
           * }
           * ```
           *
           * Roles can be granted and revoked dynamically via the {grantRole} and
           * {revokeRole} functions. Each role has an associated admin role, and only
           * accounts that have a role's admin role can call {grantRole} and {revokeRole}.
           *
           * By default, the admin role for all roles is `DEFAULT_ADMIN_ROLE`, which means
           * that only accounts with this role will be able to grant or revoke other
           * roles. More complex role relationships can be created by using
           * {_setRoleAdmin}.
           *
           * WARNING: The `DEFAULT_ADMIN_ROLE` is also its own admin: it has permission to
           * grant and revoke this role. Extra precautions should be taken to secure
           * accounts that have been granted it.
           */
          abstract contract AccessControlUpgradeable is Initializable, ContextUpgradeable, IAccessControlUpgradeable, ERC165Upgradeable {
              function __AccessControl_init() internal onlyInitializing {
              }
              function __AccessControl_init_unchained() internal onlyInitializing {
              }
              struct RoleData {
                  mapping(address => bool) members;
                  bytes32 adminRole;
              }
              mapping(bytes32 => RoleData) private _roles;
              bytes32 public constant DEFAULT_ADMIN_ROLE = 0x00;
              /**
               * @dev Modifier that checks that an account has a specific role. Reverts
               * with a standardized message including the required role.
               *
               * The format of the revert reason is given by the following regular expression:
               *
               *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
               *
               * _Available since v4.1._
               */
              modifier onlyRole(bytes32 role) {
                  _checkRole(role);
                  _;
              }
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IAccessControlUpgradeable).interfaceId || super.supportsInterface(interfaceId);
              }
              /**
               * @dev Returns `true` if `account` has been granted `role`.
               */
              function hasRole(bytes32 role, address account) public view virtual override returns (bool) {
                  return _roles[role].members[account];
              }
              /**
               * @dev Revert with a standard message if `_msgSender()` is missing `role`.
               * Overriding this function changes the behavior of the {onlyRole} modifier.
               *
               * Format of the revert message is described in {_checkRole}.
               *
               * _Available since v4.6._
               */
              function _checkRole(bytes32 role) internal view virtual {
                  _checkRole(role, _msgSender());
              }
              /**
               * @dev Revert with a standard message if `account` is missing `role`.
               *
               * The format of the revert reason is given by the following regular expression:
               *
               *  /^AccessControl: account (0x[0-9a-f]{40}) is missing role (0x[0-9a-f]{64})$/
               */
              function _checkRole(bytes32 role, address account) internal view virtual {
                  if (!hasRole(role, account)) {
                      revert(
                          string(
                              abi.encodePacked(
                                  "AccessControl: account ",
                                  StringsUpgradeable.toHexString(account),
                                  " is missing role ",
                                  StringsUpgradeable.toHexString(uint256(role), 32)
                              )
                          )
                      );
                  }
              }
              /**
               * @dev Returns the admin role that controls `role`. See {grantRole} and
               * {revokeRole}.
               *
               * To change a role's admin, use {_setRoleAdmin}.
               */
              function getRoleAdmin(bytes32 role) public view virtual override returns (bytes32) {
                  return _roles[role].adminRole;
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               *
               * May emit a {RoleGranted} event.
               */
              function grantRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                  _grantRole(role, account);
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               *
               * May emit a {RoleRevoked} event.
               */
              function revokeRole(bytes32 role, address account) public virtual override onlyRole(getRoleAdmin(role)) {
                  _revokeRole(role, account);
              }
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Roles are often managed via {grantRole} and {revokeRole}: this function's
               * purpose is to provide a mechanism for accounts to lose their privileges
               * if they are compromised (such as when a trusted device is misplaced).
               *
               * If the calling account had been revoked `role`, emits a {RoleRevoked}
               * event.
               *
               * Requirements:
               *
               * - the caller must be `account`.
               *
               * May emit a {RoleRevoked} event.
               */
              function renounceRole(bytes32 role, address account) public virtual override {
                  require(account == _msgSender(), "AccessControl: can only renounce roles for self");
                  _revokeRole(role, account);
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event. Note that unlike {grantRole}, this function doesn't perform any
               * checks on the calling account.
               *
               * May emit a {RoleGranted} event.
               *
               * [WARNING]
               * ====
               * This function should only be called from the constructor when setting
               * up the initial roles for the system.
               *
               * Using this function in any other way is effectively circumventing the admin
               * system imposed by {AccessControl}.
               * ====
               *
               * NOTE: This function is deprecated in favor of {_grantRole}.
               */
              function _setupRole(bytes32 role, address account) internal virtual {
                  _grantRole(role, account);
              }
              /**
               * @dev Sets `adminRole` as ``role``'s admin role.
               *
               * Emits a {RoleAdminChanged} event.
               */
              function _setRoleAdmin(bytes32 role, bytes32 adminRole) internal virtual {
                  bytes32 previousAdminRole = getRoleAdmin(role);
                  _roles[role].adminRole = adminRole;
                  emit RoleAdminChanged(role, previousAdminRole, adminRole);
              }
              /**
               * @dev Grants `role` to `account`.
               *
               * Internal function without access restriction.
               *
               * May emit a {RoleGranted} event.
               */
              function _grantRole(bytes32 role, address account) internal virtual {
                  if (!hasRole(role, account)) {
                      _roles[role].members[account] = true;
                      emit RoleGranted(role, account, _msgSender());
                  }
              }
              /**
               * @dev Revokes `role` from `account`.
               *
               * Internal function without access restriction.
               *
               * May emit a {RoleRevoked} event.
               */
              function _revokeRole(bytes32 role, address account) internal virtual {
                  if (hasRole(role, account)) {
                      _roles[role].members[account] = false;
                      emit RoleRevoked(role, account, _msgSender());
                  }
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[49] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (access/IAccessControl.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev External interface of AccessControl declared to support ERC165 detection.
           */
          interface IAccessControlUpgradeable {
              /**
               * @dev Emitted when `newAdminRole` is set as ``role``'s admin role, replacing `previousAdminRole`
               *
               * `DEFAULT_ADMIN_ROLE` is the starting admin for all roles, despite
               * {RoleAdminChanged} not being emitted signaling this.
               *
               * _Available since v3.1._
               */
              event RoleAdminChanged(bytes32 indexed role, bytes32 indexed previousAdminRole, bytes32 indexed newAdminRole);
              /**
               * @dev Emitted when `account` is granted `role`.
               *
               * `sender` is the account that originated the contract call, an admin role
               * bearer except when using {AccessControl-_setupRole}.
               */
              event RoleGranted(bytes32 indexed role, address indexed account, address indexed sender);
              /**
               * @dev Emitted when `account` is revoked `role`.
               *
               * `sender` is the account that originated the contract call:
               *   - if using `revokeRole`, it is the admin role bearer
               *   - if using `renounceRole`, it is the role bearer (i.e. `account`)
               */
              event RoleRevoked(bytes32 indexed role, address indexed account, address indexed sender);
              /**
               * @dev Returns `true` if `account` has been granted `role`.
               */
              function hasRole(bytes32 role, address account) external view returns (bool);
              /**
               * @dev Returns the admin role that controls `role`. See {grantRole} and
               * {revokeRole}.
               *
               * To change a role's admin, use {AccessControl-_setRoleAdmin}.
               */
              function getRoleAdmin(bytes32 role) external view returns (bytes32);
              /**
               * @dev Grants `role` to `account`.
               *
               * If `account` had not been already granted `role`, emits a {RoleGranted}
               * event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function grantRole(bytes32 role, address account) external;
              /**
               * @dev Revokes `role` from `account`.
               *
               * If `account` had been granted `role`, emits a {RoleRevoked} event.
               *
               * Requirements:
               *
               * - the caller must have ``role``'s admin role.
               */
              function revokeRole(bytes32 role, address account) external;
              /**
               * @dev Revokes `role` from the calling account.
               *
               * Roles are often managed via {grantRole} and {revokeRole}: this function's
               * purpose is to provide a mechanism for accounts to lose their privileges
               * if they are compromised (such as when a trusted device is misplaced).
               *
               * If the calling account had been granted `role`, emits a {RoleRevoked}
               * event.
               *
               * Requirements:
               *
               * - the caller must be `account`.
               */
              function renounceRole(bytes32 role, address account) external;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (interfaces/draft-IERC1822.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
           * proxy whose upgrades are fully controlled by the current implementation.
           */
          interface IERC1822ProxiableUpgradeable {
              /**
               * @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
               * address.
               *
               * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
               * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
               * function revert if invoked through a proxy.
               */
              function proxiableUUID() external view returns (bytes32);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev This is the interface that {BeaconProxy} expects of its beacon.
           */
          interface IBeaconUpgradeable {
              /**
               * @dev Must return an address that can be used as a delegate call target.
               *
               * {BeaconProxy} will check that this address is a contract.
               */
              function implementation() external view returns (address);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (proxy/ERC1967/ERC1967Upgrade.sol)
          pragma solidity ^0.8.2;
          import "../beacon/IBeaconUpgradeable.sol";
          import "../../interfaces/draft-IERC1822Upgradeable.sol";
          import "../../utils/AddressUpgradeable.sol";
          import "../../utils/StorageSlotUpgradeable.sol";
          import "../utils/Initializable.sol";
          /**
           * @dev This abstract contract provides getters and event emitting update functions for
           * https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
           *
           * _Available since v4.1._
           *
           * @custom:oz-upgrades-unsafe-allow delegatecall
           */
          abstract contract ERC1967UpgradeUpgradeable is Initializable {
              function __ERC1967Upgrade_init() internal onlyInitializing {
              }
              function __ERC1967Upgrade_init_unchained() internal onlyInitializing {
              }
              // This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
              bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
              /**
               * @dev Storage slot with the address of the current implementation.
               * This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
              /**
               * @dev Emitted when the implementation is upgraded.
               */
              event Upgraded(address indexed implementation);
              /**
               * @dev Returns the current implementation address.
               */
              function _getImplementation() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value;
              }
              /**
               * @dev Stores a new address in the EIP1967 implementation slot.
               */
              function _setImplementation(address newImplementation) private {
                  require(AddressUpgradeable.isContract(newImplementation), "ERC1967: new implementation is not a contract");
                  StorageSlotUpgradeable.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
              }
              /**
               * @dev Perform implementation upgrade
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeTo(address newImplementation) internal {
                  _setImplementation(newImplementation);
                  emit Upgraded(newImplementation);
              }
              /**
               * @dev Perform implementation upgrade with additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCall(
                  address newImplementation,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  _upgradeTo(newImplementation);
                  if (data.length > 0 || forceCall) {
                      _functionDelegateCall(newImplementation, data);
                  }
              }
              /**
               * @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
               *
               * Emits an {Upgraded} event.
               */
              function _upgradeToAndCallUUPS(
                  address newImplementation,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  // Upgrades from old implementations will perform a rollback test. This test requires the new
                  // implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
                  // this special case will break upgrade paths from old UUPS implementation to new ones.
                  if (StorageSlotUpgradeable.getBooleanSlot(_ROLLBACK_SLOT).value) {
                      _setImplementation(newImplementation);
                  } else {
                      try IERC1822ProxiableUpgradeable(newImplementation).proxiableUUID() returns (bytes32 slot) {
                          require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
                      } catch {
                          revert("ERC1967Upgrade: new implementation is not UUPS");
                      }
                      _upgradeToAndCall(newImplementation, data, forceCall);
                  }
              }
              /**
               * @dev Storage slot with the admin of the contract.
               * This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
               * validated in the constructor.
               */
              bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
              /**
               * @dev Emitted when the admin account has changed.
               */
              event AdminChanged(address previousAdmin, address newAdmin);
              /**
               * @dev Returns the current admin.
               */
              function _getAdmin() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value;
              }
              /**
               * @dev Stores a new address in the EIP1967 admin slot.
               */
              function _setAdmin(address newAdmin) private {
                  require(newAdmin != address(0), "ERC1967: new admin is the zero address");
                  StorageSlotUpgradeable.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
              }
              /**
               * @dev Changes the admin of the proxy.
               *
               * Emits an {AdminChanged} event.
               */
              function _changeAdmin(address newAdmin) internal {
                  emit AdminChanged(_getAdmin(), newAdmin);
                  _setAdmin(newAdmin);
              }
              /**
               * @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
               * This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
               */
              bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
              /**
               * @dev Emitted when the beacon is upgraded.
               */
              event BeaconUpgraded(address indexed beacon);
              /**
               * @dev Returns the current beacon.
               */
              function _getBeacon() internal view returns (address) {
                  return StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value;
              }
              /**
               * @dev Stores a new beacon in the EIP1967 beacon slot.
               */
              function _setBeacon(address newBeacon) private {
                  require(AddressUpgradeable.isContract(newBeacon), "ERC1967: new beacon is not a contract");
                  require(
                      AddressUpgradeable.isContract(IBeaconUpgradeable(newBeacon).implementation()),
                      "ERC1967: beacon implementation is not a contract"
                  );
                  StorageSlotUpgradeable.getAddressSlot(_BEACON_SLOT).value = newBeacon;
              }
              /**
               * @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
               * not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
               *
               * Emits a {BeaconUpgraded} event.
               */
              function _upgradeBeaconToAndCall(
                  address newBeacon,
                  bytes memory data,
                  bool forceCall
              ) internal {
                  _setBeacon(newBeacon);
                  emit BeaconUpgraded(newBeacon);
                  if (data.length > 0 || forceCall) {
                      _functionDelegateCall(IBeaconUpgradeable(newBeacon).implementation(), data);
                  }
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a delegate call.
               *
               * _Available since v3.4._
               */
              function _functionDelegateCall(address target, bytes memory data) private returns (bytes memory) {
                  require(AddressUpgradeable.isContract(target), "Address: delegate call to non-contract");
                  // solhint-disable-next-line avoid-low-level-calls
                  (bool success, bytes memory returndata) = target.delegatecall(data);
                  return AddressUpgradeable.verifyCallResult(success, returndata, "Address: low-level delegate call failed");
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (proxy/utils/Initializable.sol)
          pragma solidity ^0.8.2;
          import "../../utils/AddressUpgradeable.sol";
          /**
           * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
           * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
           * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
           * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
           *
           * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
           * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
           * case an upgrade adds a module that needs to be initialized.
           *
           * For example:
           *
           * [.hljs-theme-light.nopadding]
           * ```
           * contract MyToken is ERC20Upgradeable {
           *     function initialize() initializer public {
           *         __ERC20_init("MyToken", "MTK");
           *     }
           * }
           * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
           *     function initializeV2() reinitializer(2) public {
           *         __ERC20Permit_init("MyToken");
           *     }
           * }
           * ```
           *
           * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
           * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
           *
           * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
           * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
           *
           * [CAUTION]
           * ====
           * Avoid leaving a contract uninitialized.
           *
           * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
           * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
           * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
           *
           * [.hljs-theme-light.nopadding]
           * ```
           * /// @custom:oz-upgrades-unsafe-allow constructor
           * constructor() {
           *     _disableInitializers();
           * }
           * ```
           * ====
           */
          abstract contract Initializable {
              /**
               * @dev Indicates that the contract has been initialized.
               * @custom:oz-retyped-from bool
               */
              uint8 private _initialized;
              /**
               * @dev Indicates that the contract is in the process of being initialized.
               */
              bool private _initializing;
              /**
               * @dev Triggered when the contract has been initialized or reinitialized.
               */
              event Initialized(uint8 version);
              /**
               * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
               * `onlyInitializing` functions can be used to initialize parent contracts.
               *
               * Similar to `reinitializer(1)`, except that functions marked with `initializer` can be nested in the context of a
               * constructor.
               *
               * Emits an {Initialized} event.
               */
              modifier initializer() {
                  bool isTopLevelCall = !_initializing;
                  require(
                      (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                      "Initializable: contract is already initialized"
                  );
                  _initialized = 1;
                  if (isTopLevelCall) {
                      _initializing = true;
                  }
                  _;
                  if (isTopLevelCall) {
                      _initializing = false;
                      emit Initialized(1);
                  }
              }
              /**
               * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
               * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
               * used to initialize parent contracts.
               *
               * A reinitializer may be used after the original initialization step. This is essential to configure modules that
               * are added through upgrades and that require initialization.
               *
               * When `version` is 1, this modifier is similar to `initializer`, except that functions marked with `reinitializer`
               * cannot be nested. If one is invoked in the context of another, execution will revert.
               *
               * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
               * a contract, executing them in the right order is up to the developer or operator.
               *
               * WARNING: setting the version to 255 will prevent any future reinitialization.
               *
               * Emits an {Initialized} event.
               */
              modifier reinitializer(uint8 version) {
                  require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
                  _initialized = version;
                  _initializing = true;
                  _;
                  _initializing = false;
                  emit Initialized(version);
              }
              /**
               * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
               * {initializer} and {reinitializer} modifiers, directly or indirectly.
               */
              modifier onlyInitializing() {
                  require(_initializing, "Initializable: contract is not initializing");
                  _;
              }
              /**
               * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
               * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
               * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
               * through proxies.
               *
               * Emits an {Initialized} event the first time it is successfully executed.
               */
              function _disableInitializers() internal virtual {
                  require(!_initializing, "Initializable: contract is initializing");
                  if (_initialized < type(uint8).max) {
                      _initialized = type(uint8).max;
                      emit Initialized(type(uint8).max);
                  }
              }
              /**
               * @dev Internal function that returns the initialized version. Returns `_initialized`
               */
              function _getInitializedVersion() internal view returns (uint8) {
                  return _initialized;
              }
              /**
               * @dev Internal function that returns the initialized version. Returns `_initializing`
               */
              function _isInitializing() internal view returns (bool) {
                  return _initializing;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (proxy/utils/UUPSUpgradeable.sol)
          pragma solidity ^0.8.0;
          import "../../interfaces/draft-IERC1822Upgradeable.sol";
          import "../ERC1967/ERC1967UpgradeUpgradeable.sol";
          import "./Initializable.sol";
          /**
           * @dev An upgradeability mechanism designed for UUPS proxies. The functions included here can perform an upgrade of an
           * {ERC1967Proxy}, when this contract is set as the implementation behind such a proxy.
           *
           * A security mechanism ensures that an upgrade does not turn off upgradeability accidentally, although this risk is
           * reinstated if the upgrade retains upgradeability but removes the security mechanism, e.g. by replacing
           * `UUPSUpgradeable` with a custom implementation of upgrades.
           *
           * The {_authorizeUpgrade} function must be overridden to include access restriction to the upgrade mechanism.
           *
           * _Available since v4.1._
           */
          abstract contract UUPSUpgradeable is Initializable, IERC1822ProxiableUpgradeable, ERC1967UpgradeUpgradeable {
              function __UUPSUpgradeable_init() internal onlyInitializing {
              }
              function __UUPSUpgradeable_init_unchained() internal onlyInitializing {
              }
              /// @custom:oz-upgrades-unsafe-allow state-variable-immutable state-variable-assignment
              address private immutable __self = address(this);
              /**
               * @dev Check that the execution is being performed through a delegatecall call and that the execution context is
               * a proxy contract with an implementation (as defined in ERC1967) pointing to self. This should only be the case
               * for UUPS and transparent proxies that are using the current contract as their implementation. Execution of a
               * function through ERC1167 minimal proxies (clones) would not normally pass this test, but is not guaranteed to
               * fail.
               */
              modifier onlyProxy() {
                  require(address(this) != __self, "Function must be called through delegatecall");
                  require(_getImplementation() == __self, "Function must be called through active proxy");
                  _;
              }
              /**
               * @dev Check that the execution is not being performed through a delegate call. This allows a function to be
               * callable on the implementing contract but not through proxies.
               */
              modifier notDelegated() {
                  require(address(this) == __self, "UUPSUpgradeable: must not be called through delegatecall");
                  _;
              }
              /**
               * @dev Implementation of the ERC1822 {proxiableUUID} function. This returns the storage slot used by the
               * implementation. It is used to validate the implementation's compatibility when performing an upgrade.
               *
               * IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
               * bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
               * function revert if invoked through a proxy. This is guaranteed by the `notDelegated` modifier.
               */
              function proxiableUUID() external view virtual override notDelegated returns (bytes32) {
                  return _IMPLEMENTATION_SLOT;
              }
              /**
               * @dev Upgrade the implementation of the proxy to `newImplementation`.
               *
               * Calls {_authorizeUpgrade}.
               *
               * Emits an {Upgraded} event.
               */
              function upgradeTo(address newImplementation) external virtual onlyProxy {
                  _authorizeUpgrade(newImplementation);
                  _upgradeToAndCallUUPS(newImplementation, new bytes(0), false);
              }
              /**
               * @dev Upgrade the implementation of the proxy to `newImplementation`, and subsequently execute the function call
               * encoded in `data`.
               *
               * Calls {_authorizeUpgrade}.
               *
               * Emits an {Upgraded} event.
               */
              function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual onlyProxy {
                  _authorizeUpgrade(newImplementation);
                  _upgradeToAndCallUUPS(newImplementation, data, true);
              }
              /**
               * @dev Function that should revert when `msg.sender` is not authorized to upgrade the contract. Called by
               * {upgradeTo} and {upgradeToAndCall}.
               *
               * Normally, this function will use an xref:access.adoc[access control] modifier such as {Ownable-onlyOwner}.
               *
               * ```solidity
               * function _authorizeUpgrade(address) internal override onlyOwner {}
               * ```
               */
              function _authorizeUpgrade(address newImplementation) internal virtual;
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (security/Pausable.sol)
          pragma solidity ^0.8.0;
          import "../utils/ContextUpgradeable.sol";
          import "../proxy/utils/Initializable.sol";
          /**
           * @dev Contract module which allows children to implement an emergency stop
           * mechanism that can be triggered by an authorized account.
           *
           * This module is used through inheritance. It will make available the
           * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
           * the functions of your contract. Note that they will not be pausable by
           * simply including this module, only once the modifiers are put in place.
           */
          abstract contract PausableUpgradeable is Initializable, ContextUpgradeable {
              /**
               * @dev Emitted when the pause is triggered by `account`.
               */
              event Paused(address account);
              /**
               * @dev Emitted when the pause is lifted by `account`.
               */
              event Unpaused(address account);
              bool private _paused;
              /**
               * @dev Initializes the contract in unpaused state.
               */
              function __Pausable_init() internal onlyInitializing {
                  __Pausable_init_unchained();
              }
              function __Pausable_init_unchained() internal onlyInitializing {
                  _paused = false;
              }
              /**
               * @dev Modifier to make a function callable only when the contract is not paused.
               *
               * Requirements:
               *
               * - The contract must not be paused.
               */
              modifier whenNotPaused() {
                  _requireNotPaused();
                  _;
              }
              /**
               * @dev Modifier to make a function callable only when the contract is paused.
               *
               * Requirements:
               *
               * - The contract must be paused.
               */
              modifier whenPaused() {
                  _requirePaused();
                  _;
              }
              /**
               * @dev Returns true if the contract is paused, and false otherwise.
               */
              function paused() public view virtual returns (bool) {
                  return _paused;
              }
              /**
               * @dev Throws if the contract is paused.
               */
              function _requireNotPaused() internal view virtual {
                  require(!paused(), "Pausable: paused");
              }
              /**
               * @dev Throws if the contract is not paused.
               */
              function _requirePaused() internal view virtual {
                  require(paused(), "Pausable: not paused");
              }
              /**
               * @dev Triggers stopped state.
               *
               * Requirements:
               *
               * - The contract must not be paused.
               */
              function _pause() internal virtual whenNotPaused {
                  _paused = true;
                  emit Paused(_msgSender());
              }
              /**
               * @dev Returns to normal state.
               *
               * Requirements:
               *
               * - The contract must be paused.
               */
              function _unpause() internal virtual whenPaused {
                  _paused = false;
                  emit Unpaused(_msgSender());
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[49] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/ERC20.sol)
          pragma solidity ^0.8.0;
          import "./IERC20Upgradeable.sol";
          import "./extensions/IERC20MetadataUpgradeable.sol";
          import "../../utils/ContextUpgradeable.sol";
          import "../../proxy/utils/Initializable.sol";
          /**
           * @dev Implementation of the {IERC20} interface.
           *
           * This implementation is agnostic to the way tokens are created. This means
           * that a supply mechanism has to be added in a derived contract using {_mint}.
           * For a generic mechanism see {ERC20PresetMinterPauser}.
           *
           * TIP: For a detailed writeup see our guide
           * https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
           * to implement supply mechanisms].
           *
           * We have followed general OpenZeppelin Contracts guidelines: functions revert
           * instead returning `false` on failure. This behavior is nonetheless
           * conventional and does not conflict with the expectations of ERC20
           * applications.
           *
           * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
           * This allows applications to reconstruct the allowance for all accounts just
           * by listening to said events. Other implementations of the EIP may not emit
           * these events, as it isn't required by the specification.
           *
           * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
           * functions have been added to mitigate the well-known issues around setting
           * allowances. See {IERC20-approve}.
           */
          contract ERC20Upgradeable is Initializable, ContextUpgradeable, IERC20Upgradeable, IERC20MetadataUpgradeable {
              mapping(address => uint256) private _balances;
              mapping(address => mapping(address => uint256)) private _allowances;
              uint256 private _totalSupply;
              string private _name;
              string private _symbol;
              /**
               * @dev Sets the values for {name} and {symbol}.
               *
               * The default value of {decimals} is 18. To select a different value for
               * {decimals} you should overload it.
               *
               * All two of these values are immutable: they can only be set once during
               * construction.
               */
              function __ERC20_init(string memory name_, string memory symbol_) internal onlyInitializing {
                  __ERC20_init_unchained(name_, symbol_);
              }
              function __ERC20_init_unchained(string memory name_, string memory symbol_) internal onlyInitializing {
                  _name = name_;
                  _symbol = symbol_;
              }
              /**
               * @dev Returns the name of the token.
               */
              function name() public view virtual override returns (string memory) {
                  return _name;
              }
              /**
               * @dev Returns the symbol of the token, usually a shorter version of the
               * name.
               */
              function symbol() public view virtual override returns (string memory) {
                  return _symbol;
              }
              /**
               * @dev Returns the number of decimals used to get its user representation.
               * For example, if `decimals` equals `2`, a balance of `505` tokens should
               * be displayed to a user as `5.05` (`505 / 10 ** 2`).
               *
               * Tokens usually opt for a value of 18, imitating the relationship between
               * Ether and Wei. This is the value {ERC20} uses, unless this function is
               * overridden;
               *
               * NOTE: This information is only used for _display_ purposes: it in
               * no way affects any of the arithmetic of the contract, including
               * {IERC20-balanceOf} and {IERC20-transfer}.
               */
              function decimals() public view virtual override returns (uint8) {
                  return 18;
              }
              /**
               * @dev See {IERC20-totalSupply}.
               */
              function totalSupply() public view virtual override returns (uint256) {
                  return _totalSupply;
              }
              /**
               * @dev See {IERC20-balanceOf}.
               */
              function balanceOf(address account) public view virtual override returns (uint256) {
                  return _balances[account];
              }
              /**
               * @dev See {IERC20-transfer}.
               *
               * Requirements:
               *
               * - `to` cannot be the zero address.
               * - the caller must have a balance of at least `amount`.
               */
              function transfer(address to, uint256 amount) public virtual override returns (bool) {
                  address owner = _msgSender();
                  _transfer(owner, to, amount);
                  return true;
              }
              /**
               * @dev See {IERC20-allowance}.
               */
              function allowance(address owner, address spender) public view virtual override returns (uint256) {
                  return _allowances[owner][spender];
              }
              /**
               * @dev See {IERC20-approve}.
               *
               * NOTE: If `amount` is the maximum `uint256`, the allowance is not updated on
               * `transferFrom`. This is semantically equivalent to an infinite approval.
               *
               * Requirements:
               *
               * - `spender` cannot be the zero address.
               */
              function approve(address spender, uint256 amount) public virtual override returns (bool) {
                  address owner = _msgSender();
                  _approve(owner, spender, amount);
                  return true;
              }
              /**
               * @dev See {IERC20-transferFrom}.
               *
               * Emits an {Approval} event indicating the updated allowance. This is not
               * required by the EIP. See the note at the beginning of {ERC20}.
               *
               * NOTE: Does not update the allowance if the current allowance
               * is the maximum `uint256`.
               *
               * Requirements:
               *
               * - `from` and `to` cannot be the zero address.
               * - `from` must have a balance of at least `amount`.
               * - the caller must have allowance for ``from``'s tokens of at least
               * `amount`.
               */
              function transferFrom(
                  address from,
                  address to,
                  uint256 amount
              ) public virtual override returns (bool) {
                  address spender = _msgSender();
                  _spendAllowance(from, spender, amount);
                  _transfer(from, to, amount);
                  return true;
              }
              /**
               * @dev Atomically increases the allowance granted to `spender` by the caller.
               *
               * This is an alternative to {approve} that can be used as a mitigation for
               * problems described in {IERC20-approve}.
               *
               * Emits an {Approval} event indicating the updated allowance.
               *
               * Requirements:
               *
               * - `spender` cannot be the zero address.
               */
              function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
                  address owner = _msgSender();
                  _approve(owner, spender, allowance(owner, spender) + addedValue);
                  return true;
              }
              /**
               * @dev Atomically decreases the allowance granted to `spender` by the caller.
               *
               * This is an alternative to {approve} that can be used as a mitigation for
               * problems described in {IERC20-approve}.
               *
               * Emits an {Approval} event indicating the updated allowance.
               *
               * Requirements:
               *
               * - `spender` cannot be the zero address.
               * - `spender` must have allowance for the caller of at least
               * `subtractedValue`.
               */
              function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
                  address owner = _msgSender();
                  uint256 currentAllowance = allowance(owner, spender);
                  require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
                  unchecked {
                      _approve(owner, spender, currentAllowance - subtractedValue);
                  }
                  return true;
              }
              /**
               * @dev Moves `amount` of tokens from `from` to `to`.
               *
               * This internal function is equivalent to {transfer}, and can be used to
               * e.g. implement automatic token fees, slashing mechanisms, etc.
               *
               * Emits a {Transfer} event.
               *
               * Requirements:
               *
               * - `from` cannot be the zero address.
               * - `to` cannot be the zero address.
               * - `from` must have a balance of at least `amount`.
               */
              function _transfer(
                  address from,
                  address to,
                  uint256 amount
              ) internal virtual {
                  require(from != address(0), "ERC20: transfer from the zero address");
                  require(to != address(0), "ERC20: transfer to the zero address");
                  _beforeTokenTransfer(from, to, amount);
                  uint256 fromBalance = _balances[from];
                  require(fromBalance >= amount, "ERC20: transfer amount exceeds balance");
                  unchecked {
                      _balances[from] = fromBalance - amount;
                      // Overflow not possible: the sum of all balances is capped by totalSupply, and the sum is preserved by
                      // decrementing then incrementing.
                      _balances[to] += amount;
                  }
                  emit Transfer(from, to, amount);
                  _afterTokenTransfer(from, to, amount);
              }
              /** @dev Creates `amount` tokens and assigns them to `account`, increasing
               * the total supply.
               *
               * Emits a {Transfer} event with `from` set to the zero address.
               *
               * Requirements:
               *
               * - `account` cannot be the zero address.
               */
              function _mint(address account, uint256 amount) internal virtual {
                  require(account != address(0), "ERC20: mint to the zero address");
                  _beforeTokenTransfer(address(0), account, amount);
                  _totalSupply += amount;
                  unchecked {
                      // Overflow not possible: balance + amount is at most totalSupply + amount, which is checked above.
                      _balances[account] += amount;
                  }
                  emit Transfer(address(0), account, amount);
                  _afterTokenTransfer(address(0), account, amount);
              }
              /**
               * @dev Destroys `amount` tokens from `account`, reducing the
               * total supply.
               *
               * Emits a {Transfer} event with `to` set to the zero address.
               *
               * Requirements:
               *
               * - `account` cannot be the zero address.
               * - `account` must have at least `amount` tokens.
               */
              function _burn(address account, uint256 amount) internal virtual {
                  require(account != address(0), "ERC20: burn from the zero address");
                  _beforeTokenTransfer(account, address(0), amount);
                  uint256 accountBalance = _balances[account];
                  require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
                  unchecked {
                      _balances[account] = accountBalance - amount;
                      // Overflow not possible: amount <= accountBalance <= totalSupply.
                      _totalSupply -= amount;
                  }
                  emit Transfer(account, address(0), amount);
                  _afterTokenTransfer(account, address(0), amount);
              }
              /**
               * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
               *
               * This internal function is equivalent to `approve`, and can be used to
               * e.g. set automatic allowances for certain subsystems, etc.
               *
               * Emits an {Approval} event.
               *
               * Requirements:
               *
               * - `owner` cannot be the zero address.
               * - `spender` cannot be the zero address.
               */
              function _approve(
                  address owner,
                  address spender,
                  uint256 amount
              ) internal virtual {
                  require(owner != address(0), "ERC20: approve from the zero address");
                  require(spender != address(0), "ERC20: approve to the zero address");
                  _allowances[owner][spender] = amount;
                  emit Approval(owner, spender, amount);
              }
              /**
               * @dev Updates `owner` s allowance for `spender` based on spent `amount`.
               *
               * Does not update the allowance amount in case of infinite allowance.
               * Revert if not enough allowance is available.
               *
               * Might emit an {Approval} event.
               */
              function _spendAllowance(
                  address owner,
                  address spender,
                  uint256 amount
              ) internal virtual {
                  uint256 currentAllowance = allowance(owner, spender);
                  if (currentAllowance != type(uint256).max) {
                      require(currentAllowance >= amount, "ERC20: insufficient allowance");
                      unchecked {
                          _approve(owner, spender, currentAllowance - amount);
                      }
                  }
              }
              /**
               * @dev Hook that is called before any transfer of tokens. This includes
               * minting and burning.
               *
               * Calling conditions:
               *
               * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
               * will be transferred to `to`.
               * - when `from` is zero, `amount` tokens will be minted for `to`.
               * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
               * - `from` and `to` are never both zero.
               *
               * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
               */
              function _beforeTokenTransfer(
                  address from,
                  address to,
                  uint256 amount
              ) internal virtual {}
              /**
               * @dev Hook that is called after any transfer of tokens. This includes
               * minting and burning.
               *
               * Calling conditions:
               *
               * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
               * has been transferred to `to`.
               * - when `from` is zero, `amount` tokens have been minted for `to`.
               * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
               * - `from` and `to` are never both zero.
               *
               * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
               */
              function _afterTokenTransfer(
                  address from,
                  address to,
                  uint256 amount
              ) internal virtual {}
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[45] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (token/ERC20/extensions/draft-ERC20Permit.sol)
          pragma solidity ^0.8.0;
          import "./draft-IERC20PermitUpgradeable.sol";
          import "../ERC20Upgradeable.sol";
          import "../../../utils/cryptography/ECDSAUpgradeable.sol";
          import "../../../utils/cryptography/EIP712Upgradeable.sol";
          import "../../../utils/CountersUpgradeable.sol";
          import "../../../proxy/utils/Initializable.sol";
          /**
           * @dev Implementation of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
           * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
           *
           * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
           * presenting a message signed by the account. By not relying on `{IERC20-approve}`, the token holder account doesn't
           * need to send a transaction, and thus is not required to hold Ether at all.
           *
           * _Available since v3.4._
           *
           * @custom:storage-size 51
           */
          abstract contract ERC20PermitUpgradeable is Initializable, ERC20Upgradeable, IERC20PermitUpgradeable, EIP712Upgradeable {
              using CountersUpgradeable for CountersUpgradeable.Counter;
              mapping(address => CountersUpgradeable.Counter) private _nonces;
              // solhint-disable-next-line var-name-mixedcase
              bytes32 private constant _PERMIT_TYPEHASH =
                  keccak256("Permit(address owner,address spender,uint256 value,uint256 nonce,uint256 deadline)");
              /**
               * @dev In previous versions `_PERMIT_TYPEHASH` was declared as `immutable`.
               * However, to ensure consistency with the upgradeable transpiler, we will continue
               * to reserve a slot.
               * @custom:oz-renamed-from _PERMIT_TYPEHASH
               */
              // solhint-disable-next-line var-name-mixedcase
              bytes32 private _PERMIT_TYPEHASH_DEPRECATED_SLOT;
              /**
               * @dev Initializes the {EIP712} domain separator using the `name` parameter, and setting `version` to `"1"`.
               *
               * It's a good idea to use the same `name` that is defined as the ERC20 token name.
               */
              function __ERC20Permit_init(string memory name) internal onlyInitializing {
                  __EIP712_init_unchained(name, "1");
              }
              function __ERC20Permit_init_unchained(string memory) internal onlyInitializing {}
              /**
               * @dev See {IERC20Permit-permit}.
               */
              function permit(
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) public virtual override {
                  require(block.timestamp <= deadline, "ERC20Permit: expired deadline");
                  bytes32 structHash = keccak256(abi.encode(_PERMIT_TYPEHASH, owner, spender, value, _useNonce(owner), deadline));
                  bytes32 hash = _hashTypedDataV4(structHash);
                  address signer = ECDSAUpgradeable.recover(hash, v, r, s);
                  require(signer == owner, "ERC20Permit: invalid signature");
                  _approve(owner, spender, value);
              }
              /**
               * @dev See {IERC20Permit-nonces}.
               */
              function nonces(address owner) public view virtual override returns (uint256) {
                  return _nonces[owner].current();
              }
              /**
               * @dev See {IERC20Permit-DOMAIN_SEPARATOR}.
               */
              // solhint-disable-next-line func-name-mixedcase
              function DOMAIN_SEPARATOR() external view override returns (bytes32) {
                  return _domainSeparatorV4();
              }
              /**
               * @dev "Consume a nonce": return the current value and increment.
               *
               * _Available since v4.1._
               */
              function _useNonce(address owner) internal virtual returns (uint256 current) {
                  CountersUpgradeable.Counter storage nonce = _nonces[owner];
                  current = nonce.current();
                  nonce.increment();
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[49] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/draft-IERC20Permit.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC20 Permit extension allowing approvals to be made via signatures, as defined in
           * https://eips.ethereum.org/EIPS/eip-2612[EIP-2612].
           *
           * Adds the {permit} method, which can be used to change an account's ERC20 allowance (see {IERC20-allowance}) by
           * presenting a message signed by the account. By not relying on {IERC20-approve}, the token holder account doesn't
           * need to send a transaction, and thus is not required to hold Ether at all.
           */
          interface IERC20PermitUpgradeable {
              /**
               * @dev Sets `value` as the allowance of `spender` over ``owner``'s tokens,
               * given ``owner``'s signed approval.
               *
               * IMPORTANT: The same issues {IERC20-approve} has related to transaction
               * ordering also apply here.
               *
               * Emits an {Approval} event.
               *
               * Requirements:
               *
               * - `spender` cannot be the zero address.
               * - `deadline` must be a timestamp in the future.
               * - `v`, `r` and `s` must be a valid `secp256k1` signature from `owner`
               * over the EIP712-formatted function arguments.
               * - the signature must use ``owner``'s current nonce (see {nonces}).
               *
               * For more information on the signature format, see the
               * https://eips.ethereum.org/EIPS/eip-2612#specification[relevant EIP
               * section].
               */
              function permit(
                  address owner,
                  address spender,
                  uint256 value,
                  uint256 deadline,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) external;
              /**
               * @dev Returns the current nonce for `owner`. This value must be
               * included whenever a signature is generated for {permit}.
               *
               * Every successful call to {permit} increases ``owner``'s nonce by one. This
               * prevents a signature from being used multiple times.
               */
              function nonces(address owner) external view returns (uint256);
              /**
               * @dev Returns the domain separator used in the encoding of the signature for {permit}, as defined by {EIP712}.
               */
              // solhint-disable-next-line func-name-mixedcase
              function DOMAIN_SEPARATOR() external view returns (bytes32);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.5.0) (token/ERC20/extensions/ERC20Burnable.sol)
          pragma solidity ^0.8.0;
          import "../ERC20Upgradeable.sol";
          import "../../../utils/ContextUpgradeable.sol";
          import "../../../proxy/utils/Initializable.sol";
          /**
           * @dev Extension of {ERC20} that allows token holders to destroy both their own
           * tokens and those that they have an allowance for, in a way that can be
           * recognized off-chain (via event analysis).
           */
          abstract contract ERC20BurnableUpgradeable is Initializable, ContextUpgradeable, ERC20Upgradeable {
              function __ERC20Burnable_init() internal onlyInitializing {
              }
              function __ERC20Burnable_init_unchained() internal onlyInitializing {
              }
              /**
               * @dev Destroys `amount` tokens from the caller.
               *
               * See {ERC20-_burn}.
               */
              function burn(uint256 amount) public virtual {
                  _burn(_msgSender(), amount);
              }
              /**
               * @dev Destroys `amount` tokens from `account`, deducting from the caller's
               * allowance.
               *
               * See {ERC20-_burn} and {ERC20-allowance}.
               *
               * Requirements:
               *
               * - the caller must have allowance for ``accounts``'s tokens of at least
               * `amount`.
               */
              function burnFrom(address account, uint256 amount) public virtual {
                  _spendAllowance(account, _msgSender(), amount);
                  _burn(account, amount);
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (token/ERC20/extensions/IERC20Metadata.sol)
          pragma solidity ^0.8.0;
          import "../IERC20Upgradeable.sol";
          /**
           * @dev Interface for the optional metadata functions from the ERC20 standard.
           *
           * _Available since v4.1._
           */
          interface IERC20MetadataUpgradeable is IERC20Upgradeable {
              /**
               * @dev Returns the name of the token.
               */
              function name() external view returns (string memory);
              /**
               * @dev Returns the symbol of the token.
               */
              function symbol() external view returns (string memory);
              /**
               * @dev Returns the decimals places of the token.
               */
              function decimals() external view returns (uint8);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.6.0) (token/ERC20/IERC20.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC20 standard as defined in the EIP.
           */
          interface IERC20Upgradeable {
              /**
               * @dev Emitted when `value` tokens are moved from one account (`from`) to
               * another (`to`).
               *
               * Note that `value` may be zero.
               */
              event Transfer(address indexed from, address indexed to, uint256 value);
              /**
               * @dev Emitted when the allowance of a `spender` for an `owner` is set by
               * a call to {approve}. `value` is the new allowance.
               */
              event Approval(address indexed owner, address indexed spender, uint256 value);
              /**
               * @dev Returns the amount of tokens in existence.
               */
              function totalSupply() external view returns (uint256);
              /**
               * @dev Returns the amount of tokens owned by `account`.
               */
              function balanceOf(address account) external view returns (uint256);
              /**
               * @dev Moves `amount` tokens from the caller's account to `to`.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * Emits a {Transfer} event.
               */
              function transfer(address to, uint256 amount) external returns (bool);
              /**
               * @dev Returns the remaining number of tokens that `spender` will be
               * allowed to spend on behalf of `owner` through {transferFrom}. This is
               * zero by default.
               *
               * This value changes when {approve} or {transferFrom} are called.
               */
              function allowance(address owner, address spender) external view returns (uint256);
              /**
               * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * IMPORTANT: Beware that changing an allowance with this method brings the risk
               * that someone may use both the old and the new allowance by unfortunate
               * transaction ordering. One possible solution to mitigate this race
               * condition is to first reduce the spender's allowance to 0 and set the
               * desired value afterwards:
               * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
               *
               * Emits an {Approval} event.
               */
              function approve(address spender, uint256 amount) external returns (bool);
              /**
               * @dev Moves `amount` tokens from `from` to `to` using the
               * allowance mechanism. `amount` is then deducted from the caller's
               * allowance.
               *
               * Returns a boolean value indicating whether the operation succeeded.
               *
               * Emits a {Transfer} event.
               */
              function transferFrom(
                  address from,
                  address to,
                  uint256 amount
              ) external returns (bool);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/Address.sol)
          pragma solidity ^0.8.1;
          /**
           * @dev Collection of functions related to the address type
           */
          library AddressUpgradeable {
              /**
               * @dev Returns true if `account` is a contract.
               *
               * [IMPORTANT]
               * ====
               * It is unsafe to assume that an address for which this function returns
               * false is an externally-owned account (EOA) and not a contract.
               *
               * Among others, `isContract` will return false for the following
               * types of addresses:
               *
               *  - an externally-owned account
               *  - a contract in construction
               *  - an address where a contract will be created
               *  - an address where a contract lived, but was destroyed
               * ====
               *
               * [IMPORTANT]
               * ====
               * You shouldn't rely on `isContract` to protect against flash loan attacks!
               *
               * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
               * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
               * constructor.
               * ====
               */
              function isContract(address account) internal view returns (bool) {
                  // This method relies on extcodesize/address.code.length, which returns 0
                  // for contracts in construction, since the code is only stored at the end
                  // of the constructor execution.
                  return account.code.length > 0;
              }
              /**
               * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
               * `recipient`, forwarding all available gas and reverting on errors.
               *
               * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
               * of certain opcodes, possibly making contracts go over the 2300 gas limit
               * imposed by `transfer`, making them unable to receive funds via
               * `transfer`. {sendValue} removes this limitation.
               *
               * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
               *
               * IMPORTANT: because control is transferred to `recipient`, care must be
               * taken to not create reentrancy vulnerabilities. Consider using
               * {ReentrancyGuard} or the
               * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
               */
              function sendValue(address payable recipient, uint256 amount) internal {
                  require(address(this).balance >= amount, "Address: insufficient balance");
                  (bool success, ) = recipient.call{value: amount}("");
                  require(success, "Address: unable to send value, recipient may have reverted");
              }
              /**
               * @dev Performs a Solidity function call using a low level `call`. A
               * plain `call` is an unsafe replacement for a function call: use this
               * function instead.
               *
               * If `target` reverts with a revert reason, it is bubbled up by this
               * function (like regular Solidity function calls).
               *
               * Returns the raw returned data. To convert to the expected return value,
               * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
               *
               * Requirements:
               *
               * - `target` must be a contract.
               * - calling `target` with `data` must not revert.
               *
               * _Available since v3.1._
               */
              function functionCall(address target, bytes memory data) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, "Address: low-level call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
               * `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, 0, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but also transferring `value` wei to `target`.
               *
               * Requirements:
               *
               * - the calling contract must have an ETH balance of at least `value`.
               * - the called Solidity function must be `payable`.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value
              ) internal returns (bytes memory) {
                  return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
              }
              /**
               * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
               * with `errorMessage` as a fallback revert reason when `target` reverts.
               *
               * _Available since v3.1._
               */
              function functionCallWithValue(
                  address target,
                  bytes memory data,
                  uint256 value,
                  string memory errorMessage
              ) internal returns (bytes memory) {
                  require(address(this).balance >= value, "Address: insufficient balance for call");
                  (bool success, bytes memory returndata) = target.call{value: value}(data);
                  return verifyCallResultFromTarget(target, success, returndata, errorMessage);
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
                  return functionStaticCall(target, data, "Address: low-level static call failed");
              }
              /**
               * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
               * but performing a static call.
               *
               * _Available since v3.3._
               */
              function functionStaticCall(
                  address target,
                  bytes memory data,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  (bool success, bytes memory returndata) = target.staticcall(data);
                  return verifyCallResultFromTarget(target, success, returndata, errorMessage);
              }
              /**
               * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
               * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
               *
               * _Available since v4.8._
               */
              function verifyCallResultFromTarget(
                  address target,
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) internal view returns (bytes memory) {
                  if (success) {
                      if (returndata.length == 0) {
                          // only check isContract if the call was successful and the return data is empty
                          // otherwise we already know that it was a contract
                          require(isContract(target), "Address: call to non-contract");
                      }
                      return returndata;
                  } else {
                      _revert(returndata, errorMessage);
                  }
              }
              /**
               * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
               * revert reason or using the provided one.
               *
               * _Available since v4.3._
               */
              function verifyCallResult(
                  bool success,
                  bytes memory returndata,
                  string memory errorMessage
              ) internal pure returns (bytes memory) {
                  if (success) {
                      return returndata;
                  } else {
                      _revert(returndata, errorMessage);
                  }
              }
              function _revert(bytes memory returndata, string memory errorMessage) private pure {
                  // Look for revert reason and bubble it up if present
                  if (returndata.length > 0) {
                      // The easiest way to bubble the revert reason is using memory via assembly
                      /// @solidity memory-safe-assembly
                      assembly {
                          let returndata_size := mload(returndata)
                          revert(add(32, returndata), returndata_size)
                      }
                  } else {
                      revert(errorMessage);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Context.sol)
          pragma solidity ^0.8.0;
          import "../proxy/utils/Initializable.sol";
          /**
           * @dev Provides information about the current execution context, including the
           * sender of the transaction and its data. While these are generally available
           * via msg.sender and msg.data, they should not be accessed in such a direct
           * manner, since when dealing with meta-transactions the account sending and
           * paying for execution may not be the actual sender (as far as an application
           * is concerned).
           *
           * This contract is only required for intermediate, library-like contracts.
           */
          abstract contract ContextUpgradeable is Initializable {
              function __Context_init() internal onlyInitializing {
              }
              function __Context_init_unchained() internal onlyInitializing {
              }
              function _msgSender() internal view virtual returns (address) {
                  return msg.sender;
              }
              function _msgData() internal view virtual returns (bytes calldata) {
                  return msg.data;
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/Counters.sol)
          pragma solidity ^0.8.0;
          /**
           * @title Counters
           * @author Matt Condon (@shrugs)
           * @dev Provides counters that can only be incremented, decremented or reset. This can be used e.g. to track the number
           * of elements in a mapping, issuing ERC721 ids, or counting request ids.
           *
           * Include with `using Counters for Counters.Counter;`
           */
          library CountersUpgradeable {
              struct Counter {
                  // This variable should never be directly accessed by users of the library: interactions must be restricted to
                  // the library's function. As of Solidity v0.5.2, this cannot be enforced, though there is a proposal to add
                  // this feature: see https://github.com/ethereum/solidity/issues/4637
                  uint256 _value; // default: 0
              }
              function current(Counter storage counter) internal view returns (uint256) {
                  return counter._value;
              }
              function increment(Counter storage counter) internal {
                  unchecked {
                      counter._value += 1;
                  }
              }
              function decrement(Counter storage counter) internal {
                  uint256 value = counter._value;
                  require(value > 0, "Counter: decrement overflow");
                  unchecked {
                      counter._value = value - 1;
                  }
              }
              function reset(Counter storage counter) internal {
                  counter._value = 0;
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/ECDSA.sol)
          pragma solidity ^0.8.0;
          import "../StringsUpgradeable.sol";
          /**
           * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
           *
           * These functions can be used to verify that a message was signed by the holder
           * of the private keys of a given address.
           */
          library ECDSAUpgradeable {
              enum RecoverError {
                  NoError,
                  InvalidSignature,
                  InvalidSignatureLength,
                  InvalidSignatureS,
                  InvalidSignatureV // Deprecated in v4.8
              }
              function _throwError(RecoverError error) private pure {
                  if (error == RecoverError.NoError) {
                      return; // no error: do nothing
                  } else if (error == RecoverError.InvalidSignature) {
                      revert("ECDSA: invalid signature");
                  } else if (error == RecoverError.InvalidSignatureLength) {
                      revert("ECDSA: invalid signature length");
                  } else if (error == RecoverError.InvalidSignatureS) {
                      revert("ECDSA: invalid signature 's' value");
                  }
              }
              /**
               * @dev Returns the address that signed a hashed message (`hash`) with
               * `signature` or error string. This address can then be used for verification purposes.
               *
               * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
               * this function rejects them by requiring the `s` value to be in the lower
               * half order, and the `v` value to be either 27 or 28.
               *
               * IMPORTANT: `hash` _must_ be the result of a hash operation for the
               * verification to be secure: it is possible to craft signatures that
               * recover to arbitrary addresses for non-hashed data. A safe way to ensure
               * this is by receiving a hash of the original message (which may otherwise
               * be too long), and then calling {toEthSignedMessageHash} on it.
               *
               * Documentation for signature generation:
               * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
               * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
               *
               * _Available since v4.3._
               */
              function tryRecover(bytes32 hash, bytes memory signature) internal pure returns (address, RecoverError) {
                  if (signature.length == 65) {
                      bytes32 r;
                      bytes32 s;
                      uint8 v;
                      // ecrecover takes the signature parameters, and the only way to get them
                      // currently is to use assembly.
                      /// @solidity memory-safe-assembly
                      assembly {
                          r := mload(add(signature, 0x20))
                          s := mload(add(signature, 0x40))
                          v := byte(0, mload(add(signature, 0x60)))
                      }
                      return tryRecover(hash, v, r, s);
                  } else {
                      return (address(0), RecoverError.InvalidSignatureLength);
                  }
              }
              /**
               * @dev Returns the address that signed a hashed message (`hash`) with
               * `signature`. This address can then be used for verification purposes.
               *
               * The `ecrecover` EVM opcode allows for malleable (non-unique) signatures:
               * this function rejects them by requiring the `s` value to be in the lower
               * half order, and the `v` value to be either 27 or 28.
               *
               * IMPORTANT: `hash` _must_ be the result of a hash operation for the
               * verification to be secure: it is possible to craft signatures that
               * recover to arbitrary addresses for non-hashed data. A safe way to ensure
               * this is by receiving a hash of the original message (which may otherwise
               * be too long), and then calling {toEthSignedMessageHash} on it.
               */
              function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
                  (address recovered, RecoverError error) = tryRecover(hash, signature);
                  _throwError(error);
                  return recovered;
              }
              /**
               * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
               *
               * See https://eips.ethereum.org/EIPS/eip-2098[EIP-2098 short signatures]
               *
               * _Available since v4.3._
               */
              function tryRecover(
                  bytes32 hash,
                  bytes32 r,
                  bytes32 vs
              ) internal pure returns (address, RecoverError) {
                  bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
                  uint8 v = uint8((uint256(vs) >> 255) + 27);
                  return tryRecover(hash, v, r, s);
              }
              /**
               * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
               *
               * _Available since v4.2._
               */
              function recover(
                  bytes32 hash,
                  bytes32 r,
                  bytes32 vs
              ) internal pure returns (address) {
                  (address recovered, RecoverError error) = tryRecover(hash, r, vs);
                  _throwError(error);
                  return recovered;
              }
              /**
               * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
               * `r` and `s` signature fields separately.
               *
               * _Available since v4.3._
               */
              function tryRecover(
                  bytes32 hash,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal pure returns (address, RecoverError) {
                  // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
                  // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
                  // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
                  // signatures from current libraries generate a unique signature with an s-value in the lower half order.
                  //
                  // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
                  // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
                  // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
                  // these malleable signatures as well.
                  if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
                      return (address(0), RecoverError.InvalidSignatureS);
                  }
                  // If the signature is valid (and not malleable), return the signer address
                  address signer = ecrecover(hash, v, r, s);
                  if (signer == address(0)) {
                      return (address(0), RecoverError.InvalidSignature);
                  }
                  return (signer, RecoverError.NoError);
              }
              /**
               * @dev Overload of {ECDSA-recover} that receives the `v`,
               * `r` and `s` signature fields separately.
               */
              function recover(
                  bytes32 hash,
                  uint8 v,
                  bytes32 r,
                  bytes32 s
              ) internal pure returns (address) {
                  (address recovered, RecoverError error) = tryRecover(hash, v, r, s);
                  _throwError(error);
                  return recovered;
              }
              /**
               * @dev Returns an Ethereum Signed Message, created from a `hash`. This
               * produces hash corresponding to the one signed with the
               * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
               * JSON-RPC method as part of EIP-191.
               *
               * See {recover}.
               */
              function toEthSignedMessageHash(bytes32 hash) internal pure returns (bytes32) {
                  // 32 is the length in bytes of hash,
                  // enforced by the type signature above
                  return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
          32", hash));
              }
              /**
               * @dev Returns an Ethereum Signed Message, created from `s`. This
               * produces hash corresponding to the one signed with the
               * https://eth.wiki/json-rpc/API#eth_sign[`eth_sign`]
               * JSON-RPC method as part of EIP-191.
               *
               * See {recover}.
               */
              function toEthSignedMessageHash(bytes memory s) internal pure returns (bytes32) {
                  return keccak256(abi.encodePacked("\\x19Ethereum Signed Message:\
          ", StringsUpgradeable.toString(s.length), s));
              }
              /**
               * @dev Returns an Ethereum Signed Typed Data, created from a
               * `domainSeparator` and a `structHash`. This produces hash corresponding
               * to the one signed with the
               * https://eips.ethereum.org/EIPS/eip-712[`eth_signTypedData`]
               * JSON-RPC method as part of EIP-712.
               *
               * See {recover}.
               */
              function toTypedDataHash(bytes32 domainSeparator, bytes32 structHash) internal pure returns (bytes32) {
                  return keccak256(abi.encodePacked("\\x19\\x01", domainSeparator, structHash));
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/cryptography/EIP712.sol)
          pragma solidity ^0.8.0;
          import "./ECDSAUpgradeable.sol";
          import "../../proxy/utils/Initializable.sol";
          /**
           * @dev https://eips.ethereum.org/EIPS/eip-712[EIP 712] is a standard for hashing and signing of typed structured data.
           *
           * The encoding specified in the EIP is very generic, and such a generic implementation in Solidity is not feasible,
           * thus this contract does not implement the encoding itself. Protocols need to implement the type-specific encoding
           * they need in their contracts using a combination of `abi.encode` and `keccak256`.
           *
           * This contract implements the EIP 712 domain separator ({_domainSeparatorV4}) that is used as part of the encoding
           * scheme, and the final step of the encoding to obtain the message digest that is then signed via ECDSA
           * ({_hashTypedDataV4}).
           *
           * The implementation of the domain separator was designed to be as efficient as possible while still properly updating
           * the chain id to protect against replay attacks on an eventual fork of the chain.
           *
           * NOTE: This contract implements the version of the encoding known as "v4", as implemented by the JSON RPC method
           * https://docs.metamask.io/guide/signing-data.html[`eth_signTypedDataV4` in MetaMask].
           *
           * _Available since v3.4._
           *
           * @custom:storage-size 52
           */
          abstract contract EIP712Upgradeable is Initializable {
              /* solhint-disable var-name-mixedcase */
              bytes32 private _HASHED_NAME;
              bytes32 private _HASHED_VERSION;
              bytes32 private constant _TYPE_HASH = keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)");
              /* solhint-enable var-name-mixedcase */
              /**
               * @dev Initializes the domain separator and parameter caches.
               *
               * The meaning of `name` and `version` is specified in
               * https://eips.ethereum.org/EIPS/eip-712#definition-of-domainseparator[EIP 712]:
               *
               * - `name`: the user readable name of the signing domain, i.e. the name of the DApp or the protocol.
               * - `version`: the current major version of the signing domain.
               *
               * NOTE: These parameters cannot be changed except through a xref:learn::upgrading-smart-contracts.adoc[smart
               * contract upgrade].
               */
              function __EIP712_init(string memory name, string memory version) internal onlyInitializing {
                  __EIP712_init_unchained(name, version);
              }
              function __EIP712_init_unchained(string memory name, string memory version) internal onlyInitializing {
                  bytes32 hashedName = keccak256(bytes(name));
                  bytes32 hashedVersion = keccak256(bytes(version));
                  _HASHED_NAME = hashedName;
                  _HASHED_VERSION = hashedVersion;
              }
              /**
               * @dev Returns the domain separator for the current chain.
               */
              function _domainSeparatorV4() internal view returns (bytes32) {
                  return _buildDomainSeparator(_TYPE_HASH, _EIP712NameHash(), _EIP712VersionHash());
              }
              function _buildDomainSeparator(
                  bytes32 typeHash,
                  bytes32 nameHash,
                  bytes32 versionHash
              ) private view returns (bytes32) {
                  return keccak256(abi.encode(typeHash, nameHash, versionHash, block.chainid, address(this)));
              }
              /**
               * @dev Given an already https://eips.ethereum.org/EIPS/eip-712#definition-of-hashstruct[hashed struct], this
               * function returns the hash of the fully encoded EIP712 message for this domain.
               *
               * This hash can be used together with {ECDSA-recover} to obtain the signer of a message. For example:
               *
               * ```solidity
               * bytes32 digest = _hashTypedDataV4(keccak256(abi.encode(
               *     keccak256("Mail(address to,string contents)"),
               *     mailTo,
               *     keccak256(bytes(mailContents))
               * )));
               * address signer = ECDSA.recover(digest, signature);
               * ```
               */
              function _hashTypedDataV4(bytes32 structHash) internal view virtual returns (bytes32) {
                  return ECDSAUpgradeable.toTypedDataHash(_domainSeparatorV4(), structHash);
              }
              /**
               * @dev The hash of the name parameter for the EIP712 domain.
               *
               * NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
               * are a concern.
               */
              function _EIP712NameHash() internal virtual view returns (bytes32) {
                  return _HASHED_NAME;
              }
              /**
               * @dev The hash of the version parameter for the EIP712 domain.
               *
               * NOTE: This function reads from storage by default, but can be redefined to return a constant value if gas costs
               * are a concern.
               */
              function _EIP712VersionHash() internal virtual view returns (bytes32) {
                  return _HASHED_VERSION;
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/ERC165.sol)
          pragma solidity ^0.8.0;
          import "./IERC165Upgradeable.sol";
          import "../../proxy/utils/Initializable.sol";
          /**
           * @dev Implementation of the {IERC165} interface.
           *
           * Contracts that want to implement ERC165 should inherit from this contract and override {supportsInterface} to check
           * for the additional interface id that will be supported. For example:
           *
           * ```solidity
           * function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
           *     return interfaceId == type(MyInterface).interfaceId || super.supportsInterface(interfaceId);
           * }
           * ```
           *
           * Alternatively, {ERC165Storage} provides an easier to use but more expensive implementation.
           */
          abstract contract ERC165Upgradeable is Initializable, IERC165Upgradeable {
              function __ERC165_init() internal onlyInitializing {
              }
              function __ERC165_init_unchained() internal onlyInitializing {
              }
              /**
               * @dev See {IERC165-supportsInterface}.
               */
              function supportsInterface(bytes4 interfaceId) public view virtual override returns (bool) {
                  return interfaceId == type(IERC165Upgradeable).interfaceId;
              }
              /**
               * @dev This empty reserved space is put in place to allow future versions to add new
               * variables without shifting down storage in the inheritance chain.
               * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
               */
              uint256[50] private __gap;
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts v4.4.1 (utils/introspection/IERC165.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Interface of the ERC165 standard, as defined in the
           * https://eips.ethereum.org/EIPS/eip-165[EIP].
           *
           * Implementers can declare support of contract interfaces, which can then be
           * queried by others ({ERC165Checker}).
           *
           * For an implementation, see {ERC165}.
           */
          interface IERC165Upgradeable {
              /**
               * @dev Returns true if this contract implements the interface defined by
               * `interfaceId`. See the corresponding
               * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
               * to learn more about how these ids are created.
               *
               * This function call must use less than 30 000 gas.
               */
              function supportsInterface(bytes4 interfaceId) external view returns (bool);
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/math/Math.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Standard math utilities missing in the Solidity language.
           */
          library MathUpgradeable {
              enum Rounding {
                  Down, // Toward negative infinity
                  Up, // Toward infinity
                  Zero // Toward zero
              }
              /**
               * @dev Returns the largest of two numbers.
               */
              function max(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a > b ? a : b;
              }
              /**
               * @dev Returns the smallest of two numbers.
               */
              function min(uint256 a, uint256 b) internal pure returns (uint256) {
                  return a < b ? a : b;
              }
              /**
               * @dev Returns the average of two numbers. The result is rounded towards
               * zero.
               */
              function average(uint256 a, uint256 b) internal pure returns (uint256) {
                  // (a + b) / 2 can overflow.
                  return (a & b) + (a ^ b) / 2;
              }
              /**
               * @dev Returns the ceiling of the division of two numbers.
               *
               * This differs from standard division with `/` in that it rounds up instead
               * of rounding down.
               */
              function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
                  // (a + b - 1) / b can overflow on addition, so we distribute.
                  return a == 0 ? 0 : (a - 1) / b + 1;
              }
              /**
               * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
               * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
               * with further edits by Uniswap Labs also under MIT license.
               */
              function mulDiv(
                  uint256 x,
                  uint256 y,
                  uint256 denominator
              ) internal pure returns (uint256 result) {
                  unchecked {
                      // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                      // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                      // variables such that product = prod1 * 2^256 + prod0.
                      uint256 prod0; // Least significant 256 bits of the product
                      uint256 prod1; // Most significant 256 bits of the product
                      assembly {
                          let mm := mulmod(x, y, not(0))
                          prod0 := mul(x, y)
                          prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                      }
                      // Handle non-overflow cases, 256 by 256 division.
                      if (prod1 == 0) {
                          return prod0 / denominator;
                      }
                      // Make sure the result is less than 2^256. Also prevents denominator == 0.
                      require(denominator > prod1);
                      ///////////////////////////////////////////////
                      // 512 by 256 division.
                      ///////////////////////////////////////////////
                      // Make division exact by subtracting the remainder from [prod1 prod0].
                      uint256 remainder;
                      assembly {
                          // Compute remainder using mulmod.
                          remainder := mulmod(x, y, denominator)
                          // Subtract 256 bit number from 512 bit number.
                          prod1 := sub(prod1, gt(remainder, prod0))
                          prod0 := sub(prod0, remainder)
                      }
                      // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                      // See https://cs.stackexchange.com/q/138556/92363.
                      // Does not overflow because the denominator cannot be zero at this stage in the function.
                      uint256 twos = denominator & (~denominator + 1);
                      assembly {
                          // Divide denominator by twos.
                          denominator := div(denominator, twos)
                          // Divide [prod1 prod0] by twos.
                          prod0 := div(prod0, twos)
                          // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                          twos := add(div(sub(0, twos), twos), 1)
                      }
                      // Shift in bits from prod1 into prod0.
                      prod0 |= prod1 * twos;
                      // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                      // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                      // four bits. That is, denominator * inv = 1 mod 2^4.
                      uint256 inverse = (3 * denominator) ^ 2;
                      // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                      // in modular arithmetic, doubling the correct bits in each step.
                      inverse *= 2 - denominator * inverse; // inverse mod 2^8
                      inverse *= 2 - denominator * inverse; // inverse mod 2^16
                      inverse *= 2 - denominator * inverse; // inverse mod 2^32
                      inverse *= 2 - denominator * inverse; // inverse mod 2^64
                      inverse *= 2 - denominator * inverse; // inverse mod 2^128
                      inverse *= 2 - denominator * inverse; // inverse mod 2^256
                      // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                      // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                      // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                      // is no longer required.
                      result = prod0 * inverse;
                      return result;
                  }
              }
              /**
               * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
               */
              function mulDiv(
                  uint256 x,
                  uint256 y,
                  uint256 denominator,
                  Rounding rounding
              ) internal pure returns (uint256) {
                  uint256 result = mulDiv(x, y, denominator);
                  if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                      result += 1;
                  }
                  return result;
              }
              /**
               * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
               *
               * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
               */
              function sqrt(uint256 a) internal pure returns (uint256) {
                  if (a == 0) {
                      return 0;
                  }
                  // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
                  //
                  // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
                  // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
                  //
                  // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
                  // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
                  // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
                  //
                  // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
                  uint256 result = 1 << (log2(a) >> 1);
                  // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
                  // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
                  // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
                  // into the expected uint128 result.
                  unchecked {
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      result = (result + a / result) >> 1;
                      return min(result, a / result);
                  }
              }
              /**
               * @notice Calculates sqrt(a), following the selected rounding direction.
               */
              function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = sqrt(a);
                      return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 2, rounded down, of a positive value.
               * Returns 0 if given 0.
               */
              function log2(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >> 128 > 0) {
                          value >>= 128;
                          result += 128;
                      }
                      if (value >> 64 > 0) {
                          value >>= 64;
                          result += 64;
                      }
                      if (value >> 32 > 0) {
                          value >>= 32;
                          result += 32;
                      }
                      if (value >> 16 > 0) {
                          value >>= 16;
                          result += 16;
                      }
                      if (value >> 8 > 0) {
                          value >>= 8;
                          result += 8;
                      }
                      if (value >> 4 > 0) {
                          value >>= 4;
                          result += 4;
                      }
                      if (value >> 2 > 0) {
                          value >>= 2;
                          result += 2;
                      }
                      if (value >> 1 > 0) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log2(value);
                      return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 10, rounded down, of a positive value.
               * Returns 0 if given 0.
               */
              function log10(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >= 10**64) {
                          value /= 10**64;
                          result += 64;
                      }
                      if (value >= 10**32) {
                          value /= 10**32;
                          result += 32;
                      }
                      if (value >= 10**16) {
                          value /= 10**16;
                          result += 16;
                      }
                      if (value >= 10**8) {
                          value /= 10**8;
                          result += 8;
                      }
                      if (value >= 10**4) {
                          value /= 10**4;
                          result += 4;
                      }
                      if (value >= 10**2) {
                          value /= 10**2;
                          result += 2;
                      }
                      if (value >= 10**1) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log10(value);
                      return result + (rounding == Rounding.Up && 10**result < value ? 1 : 0);
                  }
              }
              /**
               * @dev Return the log in base 256, rounded down, of a positive value.
               * Returns 0 if given 0.
               *
               * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
               */
              function log256(uint256 value) internal pure returns (uint256) {
                  uint256 result = 0;
                  unchecked {
                      if (value >> 128 > 0) {
                          value >>= 128;
                          result += 16;
                      }
                      if (value >> 64 > 0) {
                          value >>= 64;
                          result += 8;
                      }
                      if (value >> 32 > 0) {
                          value >>= 32;
                          result += 4;
                      }
                      if (value >> 16 > 0) {
                          value >>= 16;
                          result += 2;
                      }
                      if (value >> 8 > 0) {
                          result += 1;
                      }
                  }
                  return result;
              }
              /**
               * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
               * Returns 0 if given 0.
               */
              function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
                  unchecked {
                      uint256 result = log256(value);
                      return result + (rounding == Rounding.Up && 1 << (result * 8) < value ? 1 : 0);
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.7.0) (utils/StorageSlot.sol)
          pragma solidity ^0.8.0;
          /**
           * @dev Library for reading and writing primitive types to specific storage slots.
           *
           * Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
           * This library helps with reading and writing to such slots without the need for inline assembly.
           *
           * The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
           *
           * Example usage to set ERC1967 implementation slot:
           * ```
           * contract ERC1967 {
           *     bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
           *
           *     function _getImplementation() internal view returns (address) {
           *         return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
           *     }
           *
           *     function _setImplementation(address newImplementation) internal {
           *         require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
           *         StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
           *     }
           * }
           * ```
           *
           * _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
           */
          library StorageSlotUpgradeable {
              struct AddressSlot {
                  address value;
              }
              struct BooleanSlot {
                  bool value;
              }
              struct Bytes32Slot {
                  bytes32 value;
              }
              struct Uint256Slot {
                  uint256 value;
              }
              /**
               * @dev Returns an `AddressSlot` with member `value` located at `slot`.
               */
              function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `BooleanSlot` with member `value` located at `slot`.
               */
              function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
               */
              function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      r.slot := slot
                  }
              }
              /**
               * @dev Returns an `Uint256Slot` with member `value` located at `slot`.
               */
              function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
                  /// @solidity memory-safe-assembly
                  assembly {
                      r.slot := slot
                  }
              }
          }
          // SPDX-License-Identifier: MIT
          // OpenZeppelin Contracts (last updated v4.8.0) (utils/Strings.sol)
          pragma solidity ^0.8.0;
          import "./math/MathUpgradeable.sol";
          /**
           * @dev String operations.
           */
          library StringsUpgradeable {
              bytes16 private constant _SYMBOLS = "0123456789abcdef";
              uint8 private constant _ADDRESS_LENGTH = 20;
              /**
               * @dev Converts a `uint256` to its ASCII `string` decimal representation.
               */
              function toString(uint256 value) internal pure returns (string memory) {
                  unchecked {
                      uint256 length = MathUpgradeable.log10(value) + 1;
                      string memory buffer = new string(length);
                      uint256 ptr;
                      /// @solidity memory-safe-assembly
                      assembly {
                          ptr := add(buffer, add(32, length))
                      }
                      while (true) {
                          ptr--;
                          /// @solidity memory-safe-assembly
                          assembly {
                              mstore8(ptr, byte(mod(value, 10), _SYMBOLS))
                          }
                          value /= 10;
                          if (value == 0) break;
                      }
                      return buffer;
                  }
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
               */
              function toHexString(uint256 value) internal pure returns (string memory) {
                  unchecked {
                      return toHexString(value, MathUpgradeable.log256(value) + 1);
                  }
              }
              /**
               * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
               */
              function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
                  bytes memory buffer = new bytes(2 * length + 2);
                  buffer[0] = "0";
                  buffer[1] = "x";
                  for (uint256 i = 2 * length + 1; i > 1; --i) {
                      buffer[i] = _SYMBOLS[value & 0xf];
                      value >>= 4;
                  }
                  require(value == 0, "Strings: hex length insufficient");
                  return string(buffer);
              }
              /**
               * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal representation.
               */
              function toHexString(address addr) internal pure returns (string memory) {
                  return toHexString(uint256(uint160(addr)), _ADDRESS_LENGTH);
              }
          }
          // SPDX-License-Identifier: Unlicensed
          pragma solidity 0.8.9;
          import "@openzeppelin/contracts-upgradeable/token/ERC20/ERC20Upgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/token/ERC20/extensions/ERC20BurnableUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/access/AccessControlUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/token/ERC20/extensions/draft-ERC20PermitUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
          import "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
          import "@openzeppelin/contracts-upgradeable/security/PausableUpgradeable.sol";
          contract Gala is
              Initializable,
              ERC20Upgradeable,
              ERC20BurnableUpgradeable,
              AccessControlUpgradeable,
              ERC20PermitUpgradeable,
              UUPSUpgradeable,
              PausableUpgradeable
          {
              bytes32 public constant MINTER_ROLE = keccak256("MINTER_ROLE");
              bytes32 public constant UPGRADER_ROLE = keccak256("UPGRADER_ROLE");
              bytes32 public constant BLOCKLISTER_ROLE = keccak256("BLOCKLISTER_ROLE");
              uint256 private constant _cap = 50_000_000_000 * 10**8;
              mapping(address => bool) internal blocklisted;
              event Blocklisted(address _account);
              event UnBlocklisted(address _account);
              event MinterAdded(address _account);
              event MinterRemoved(address _account);
              event UpgraderAdded(address _account);
              event UpgraderRemoved(address _account);
              event BlocklisterAdded(address _account);
              event BlocklisterRemoved(address _account);    
              event AdminTransferred(address _oldOwner, address _newOwner);
              modifier notBlocklisted(address _account) {
                  require(!blocklisted[_account], "Account is blocklisted");
                  _;
              }
              modifier notZeroAddress(address _account) {
                  require(_account != address(0), "address cannot be zero");
                  _;
              }
              /// @custom:oz-upgrades-unsafe-allow constructor
              constructor() {
                  _disableInitializers();
              }
              function initialize(
                  string calldata _name,
                  string calldata _symbol,
                  address _minter,
                  address _upgrader,
                  address _blocklister
              )
                  public
                  initializer
                  notZeroAddress(_minter)
                  notZeroAddress(_upgrader)
                  notZeroAddress(_blocklister)
              {
                  __ERC20_init(_name, _symbol);
                  __ERC20Burnable_init();
                  __AccessControl_init();
                  __ERC20Permit_init(_name);
                  __UUPSUpgradeable_init();
                  __Pausable_init();
                  _grantRole(DEFAULT_ADMIN_ROLE, _msgSender());
                  _grantRole(MINTER_ROLE, _minter);
                  _grantRole(UPGRADER_ROLE, _upgrader);
                  _grantRole(BLOCKLISTER_ROLE, _blocklister);
              }
              function mint(address _to, uint256 _amount) external onlyRole(MINTER_ROLE) {
                  require(_amount > 0, "amount must be greater than 0");
                  _mint(_to, _amount);
              }
              function mintBulk(address[] memory _accounts, uint256[] memory _amounts)
                  external
                  onlyRole(MINTER_ROLE)
                  returns (bool)
              {
                  require(
                      _accounts.length == _amounts.length,
                      "arrays must have same length"
                  );
                  for (uint256 i = 0; i < _accounts.length; i++) {
                      require(_amounts[i] > 0, "amount must be greater than 0");
                      _mint(_accounts[i], _amounts[i]);
                  }
                  return true;
              }
              function approve(address _spender, uint256 _value)
                  public
                  override
                  notBlocklisted(_msgSender())
                  notBlocklisted(_spender)
                  whenNotPaused
                  returns (bool)
              {
                  return super.approve(_spender, _value);
              }
              function decimals() public pure override returns (uint8) {
                  return 8;
              }
              function cap() public pure returns (uint256) {
                  return _cap;
              }
              function _beforeTokenTransfer(
                  address _from,
                  address _to,
                  uint256 _amount
              )
                  internal
                  override
                  notBlocklisted(_from)
                  notBlocklisted(_to)
                  notBlocklisted(_msgSender())
                  whenNotPaused
              {
                  super._beforeTokenTransfer(_from, _to, _amount);
                  //when minting tokens
                  if (_from == address(0)) {
                      require(
                          totalSupply() + _amount <= cap(),
                          "ERC20Capped: cap exceeded"
                      );
                  }
              }
              function isBlocklisted(address _account) external view returns (bool) {
                  return blocklisted[_account];
              }
              function blocklist(address _account)
                  external
                  onlyRole(BLOCKLISTER_ROLE)
                  notZeroAddress(_account)
                  whenNotPaused
              {
                  if (isMinter(_account) || isBlocklister(_account) || isUpgrader(_account)) 
                  {
                      revert("account has a role and cannot be blocklisted");
                  }        
                  
                  blocklisted[_account] = true;
                  emit Blocklisted(_account);
                  
              }
              function unBlocklist(address _account) 
              external 
              onlyRole(BLOCKLISTER_ROLE) 
              notZeroAddress(_account)
              whenNotPaused
              {
                  blocklisted[_account] = false;
                  emit UnBlocklisted(_account);
              }
              function increaseAllowance(address _spender, uint256 _increment)
                  public
                  override
                  notBlocklisted(_msgSender())
                  notBlocklisted(_spender)
                  whenNotPaused
                  returns (bool)
              {
                  return super.increaseAllowance(_spender, _increment);
              }
              function decreaseAllowance(address _spender, uint256 _decrement)
                  public
                  override
                  notBlocklisted(_msgSender())
                  notBlocklisted(_spender)
                  whenNotPaused
                  returns (bool)
              {
                  return super.decreaseAllowance(_spender, _decrement);
              }
              function permit(
                  address _owner,
                  address _spender,
                  uint256 _value,
                  uint256 _deadline,
                  uint8 _v,
                  bytes32 _r,
                  bytes32 _s
              )
                  public
                  override
                  notBlocklisted(_owner)
                  notBlocklisted(_spender)
                  whenNotPaused
              {
                  super.permit(_owner, _spender, _value, _deadline, _v, _r, _s);
              }
              function isMinter(address _account) public view returns (bool) {
                  return hasRole(MINTER_ROLE, _account);
              }
              function isUpgrader(address _account) public view returns (bool) {
                  return hasRole(UPGRADER_ROLE, _account);
              }
              function isBlocklister(address _account) public view returns (bool) {
                  return hasRole(BLOCKLISTER_ROLE, _account);
              }
              function pause() external onlyRole(DEFAULT_ADMIN_ROLE) {
                  _pause();
              }
              function unpause() external onlyRole(DEFAULT_ADMIN_ROLE) {
                  _unpause();
              }
              function addMinter(address _account) public           
              {
                  grantRole(MINTER_ROLE, _account);
                  emit MinterAdded(_account);
              }
              function removeMinter(address _account) public {
                  revokeRole(MINTER_ROLE, _account);
                  emit MinterRemoved(_account);
              }
              function addUpgrader(address _account) public         
              {
                  grantRole(UPGRADER_ROLE, _account);
                  emit UpgraderAdded(_account);
              }
              function removeUpgrader(address _account) public        
              {
                  revokeRole(UPGRADER_ROLE, _account);
                  emit UpgraderRemoved(_account);
              }
              function addBlocklister(address _account) public        
              {
                  grantRole(BLOCKLISTER_ROLE, _account);
                  emit BlocklisterAdded(_account);
              }
              function removeBlocklister(address _account) public        
              {
                  revokeRole(BLOCKLISTER_ROLE, _account);
                  emit BlocklisterRemoved(_account);
              }
              function transferAdmin(address _newOwner) public
              {
                  grantRole(DEFAULT_ADMIN_ROLE, _newOwner);
                  revokeRole(DEFAULT_ADMIN_ROLE, _msgSender());
                  emit AdminTransferred(_msgSender(), _newOwner);
              }    
              function grantRole(bytes32 role, address _account)
                  public
                  virtual
                  override
                  onlyRole(getRoleAdmin(role))
                  notBlocklisted(_account)
                  notZeroAddress(_account)
                  whenNotPaused
              {
                  _grantRole(role, _account);
              }
              function revokeRole(bytes32 role, address _account)
                  public
                  override
                  onlyRole(getRoleAdmin(role))        
                  notZeroAddress(_account)        
                  whenNotPaused
              {
                  _revokeRole(role, _account);
              }
              function _authorizeUpgrade(address _newImplementation)
                  internal
                  override
                  onlyRole(UPGRADER_ROLE)
              {}
          }