ETH Price: $2,441.61 (-4.35%)

Transaction Decoder

Block:
16831570 at Mar-15-2023 06:37:35 AM +UTC
Transaction Fee:
0.001558431098868649 ETH $3.81
Gas Used:
80,981 Gas / 19.244404229 Gwei

Emitted Events:

94 TransparentUpgradeableProxy.0x0e7bea53cb2b3130dd1aac8d56b61cc8da7ebab0432e2d1622513523d848f2e7( 0x0e7bea53cb2b3130dd1aac8d56b61cc8da7ebab0432e2d1622513523d848f2e7, 0x000000000000000000000000d99ac0681b904991169a4f398b9043781adbe0c3, 0000000000000000000000000000000000000000000000000000000000000001 )
95 GnosisSafeProxy.0x442e715f626346e8c54381002da614f62bee8d27386535b2521ec8540898556e( 0x442e715f626346e8c54381002da614f62bee8d27386535b2521ec8540898556e, bcbdef30ceca93e8c9b914f1437b0675be7d12bd673caf48d88762400e18712a, 0000000000000000000000000000000000000000000000000000000000000000 )

Account State Difference:

  Address   Before After State Difference Code
0x28e41c41...ee76d0BA9
0.007818880345623358 Eth
Nonce: 132
0.006260449246754709 Eth
Nonce: 133
0.001558431098868649
0x5112EbA9...EdaE7106a
(beaverbuild)
18.393815330005317815 Eth18.393864606247543177 Eth0.000049276242225362

Execution Trace

GnosisSafeProxy.6a761202( )
  • GnosisSafe.execTransaction( to=0x5523985926Aa12BA58DC5Ad00DDca99678D7227E, value=0, data=0x75F3974B000000000000000000000000D99AC0681B904991169A4F398B9043781ADBE0C30000000000000000000000000000000000000000000000000000000000000001, operation=0, safeTxGas=0, baseGas=0, gasPrice=0, gasToken=0x0000000000000000000000000000000000000000, refundReceiver=0x0000000000000000000000000000000000000000, signatures=0x40026A2F9582A196BB1464F597CFF7B096996DB9CA5710C93339CB4AD561D6B376196AD97841A3286323E84C336D5A70B5395CEE6A4C74D583C53CA18464EF3620E5A81103E53F983F0C087279407E5710C2F9262C2F3E5366EDDBFF7289A31C567F38A1D3F0EDC470E982C769BC055113D3E861450A26F4914D5021DC49F5868820EBC377B2217744815E2677B21BB5154F7C85C11E64E1CBC85225C5EF6E18BC5C7CFB412713DAE1410A31A6BA883321D9D16BCF0363E6DEB00673B55AD5B920AA1F ) => ( success=True )
    • Null: 0x000...001.6b770046( )
    • Null: 0x000...001.6b770046( )
    • Null: 0x000...001.6b770046( )
    • TransparentUpgradeableProxy.75f3974b( )
      • BridgeV2.setAdminPermission( _user=0xd99ac0681b904991169a4f398B9043781ADbe0C3, _permission=True )
        File 1 of 4: 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 4: TransparentUpgradeableProxy
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        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 "../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 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 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 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;
            }
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.0;
        import "../ERC1967/ERC1967Upgrade.sol";
        /**
         * @dev Base contract for building openzeppelin-upgrades compatible implementations for the {ERC1967Proxy}. It includes
         * publicly available upgrade functions that are called by the plugin and by the secure upgrade mechanism to verify
         * continuation of the upgradability.
         *
         * The {_authorizeUpgrade} function MUST be overridden to include access restriction to the upgrade mechanism.
         *
         * _Available since v4.1._
         */
        abstract contract UUPSUpgradeable is ERC1967Upgrade {
            function upgradeTo(address newImplementation) external virtual {
                _authorizeUpgrade(newImplementation);
                _upgradeToAndCallSecure(newImplementation, bytes(""), false);
            }
            function upgradeToAndCall(address newImplementation, bytes memory data) external payable virtual {
                _authorizeUpgrade(newImplementation);
                _upgradeToAndCallSecure(newImplementation, data, true);
            }
            function _authorizeUpgrade(address newImplementation) internal virtual;
        }
        // SPDX-License-Identifier: MIT
        pragma solidity ^0.8.2;
        import "@openzeppelin/contracts/proxy/utils/UUPSUpgradeable.sol";
        abstract contract Proxiable is UUPSUpgradeable {
            function _authorizeUpgrade(address newImplementation) internal override {
                _beforeUpgrade(newImplementation);
            }
            function _beforeUpgrade(address newImplementation) internal virtual;
        }
        contract ChildOfProxiable is Proxiable {
            function _beforeUpgrade(address newImplementation) internal virtual override {}
        }
        

        File 3 of 4: 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 4 of 4: BridgeV2
        // SPDX-License-Identifier: GPL-3.0
        pragma solidity ^0.8.4;
        import "@openzeppelin/contracts-upgradeable/proxy/utils/Initializable.sol";
        import "@uniswap/lib/contracts/libraries/TransferHelper.sol";
        import "@openzeppelin/contracts/utils/cryptography/SignatureChecker.sol";
        import "../../utils/AdminableUpgradeable.sol";
        import "../../utils/RevertMessageParser.sol";
        contract BridgeV2 is Initializable, AdminableUpgradeable {
            /// ** PUBLIC states **
            address public newMPC;
            address public oldMPC;
            uint256 public newMPCEffectiveTime;
            mapping(address => bool) public isTransmitter;
            /// ** EVENTS **
            event LogChangeMPC(
                address indexed oldMPC,
                address indexed newMPC,
                uint256 indexed effectiveTime,
                uint256 chainId
            );
            event SetTransmitterStatus(address indexed transmitter, bool status);
            event OracleRequest(
                address bridge,
                bytes callData,
                address receiveSide,
                address oppositeBridge,
                uint256 chainId
            );
            /// ** MODIFIERs **
            modifier onlyMPC() {
                require(msg.sender == mpc(), "BridgeV2: forbidden");
                _;
            }
            modifier onlyTransmitter() {
                require(isTransmitter[msg.sender], "BridgeV2: not a transmitter");
                _;
            }
            modifier onlyOwnerOrMPC() {
                require(
                    mpc() == msg.sender || owner() == msg.sender,
                    "BridgeV2: only owner or MPC can call"
                );
                _;
            }
            modifier onlySignedByMPC(bytes32 hash, bytes memory signature) {
                require(SignatureChecker.isValidSignatureNow(mpc(), hash, signature), "BridgeV2: invalid signature");
                _;
            }
            /// ** INITIALIZER **
            function initialize(address _mpc) public virtual initializer {
                __Ownable_init();
                newMPC = _mpc;
                newMPCEffectiveTime = block.timestamp;
            }
            /// ** VIEW functions **
            /**
             * @notice Returns MPC
             */
            function mpc() public view returns (address) {
                if (block.timestamp >= newMPCEffectiveTime) {
                    return newMPC;
                }
                return oldMPC;
            }
            /**
             * @notice Returns chain ID of block
             */
            function currentChainId() public view returns (uint256) {
                return block.chainid;
            }
            /// ** MPC functions **
            /**
             * @notice Receives requests
             */
            function receiveRequestV2(bytes memory _callData, address _receiveSide)
            external
            onlyMPC
            {
                _processRequest(_callData, _receiveSide);
            }
            /**
             * @notice Receives requests
             */
            function receiveRequestV2Signed(bytes memory _callData, address _receiveSide, bytes memory signature)
            external
            onlySignedByMPC(keccak256(bytes.concat("receiveRequestV2", _callData, bytes20(_receiveSide),
                bytes32(block.chainid), bytes20(address(this)))), signature)
            {
                _processRequest(_callData, _receiveSide);
            }
            /// ** TRANSMITTER functions **
            /**
             * @notice transmits request
             */
            function transmitRequestV2(
                bytes memory _callData,
                address _receiveSide,
                address _oppositeBridge,
                uint256 _chainId
            ) public onlyTransmitter {
                emit OracleRequest(
                    address(this),
                    _callData,
                    _receiveSide,
                    _oppositeBridge,
                    _chainId
                );
            }
            /// ** OWNER functions **
            /**
             * @notice Sets transmitter status
             */
            function setTransmitterStatus(address _transmitter, bool _status)
            external
            onlyOwner
            {
                isTransmitter[_transmitter] = _status;
                emit SetTransmitterStatus(_transmitter, _status);
            }
            /**
             * @notice Changes MPC by owner or MPC
             */
            function changeMPC(address _newMPC) external onlyOwnerOrMPC returns (bool) {
                return _changeMPC(_newMPC);
            }
            /**
             * @notice Changes MPC with signature
             */
            function changeMPCSigned(address _newMPC, bytes memory signature)
            external
            onlySignedByMPC(keccak256(bytes.concat("changeMPC", bytes20(_newMPC), bytes32(block.chainid),
                bytes20(address(this)))), signature)
            returns (bool)
            {
                return _changeMPC(_newMPC);
            }
            /**
             * @notice Withdraw fee by owner or admin
             */
            function withdrawFee(address token, address to, uint256 amount) external onlyOwnerOrAdmin returns (bool) {
                TransferHelper.safeTransfer(token, to, amount);
                return true;
            }
            /// ** Private functions **
            /**
             * @notice Private function that handles request processing
             */
            function _processRequest(bytes memory _callData, address _receiveSide)
            private
            {
                require(isTransmitter[_receiveSide], "BridgeV2: untrusted transmitter");
                (bool success, bytes memory data) = _receiveSide.call(_callData);
                if (!success) {
                    revert(RevertMessageParser.getRevertMessage(data, "BridgeV2: call failed"));
                }
            }
            /**
             * @notice Private function that changes MPC
             */
            function _changeMPC(address _newMPC) private returns (bool) {
                require(_newMPC != address(0), "BridgeV2: address(0x0)");
                oldMPC = mpc();
                newMPC = _newMPC;
                newMPCEffectiveTime = block.timestamp;
                emit LogChangeMPC(
                    oldMPC,
                    newMPC,
                    newMPCEffectiveTime,
                    currentChainId()
                );
                return true;
            }
        }// SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (proxy/utils/Initializable.sol)
        pragma solidity ^0.8.0;
        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 a proxied contract can't have 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.
         *
         * 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 initialize the implementation contract, you can either invoke the
         * initializer manually, or you can include a constructor to automatically mark it as initialized when it is deployed:
         *
         * [.hljs-theme-light.nopadding]
         * ```
         * /// @custom:oz-upgrades-unsafe-allow constructor
         * constructor() initializer {}
         * ```
         * ====
         */
        abstract contract Initializable {
            /**
             * @dev Indicates that the contract has been initialized.
             */
            bool private _initialized;
            /**
             * @dev Indicates that the contract is in the process of being initialized.
             */
            bool private _initializing;
            /**
             * @dev Modifier to protect an initializer function from being invoked twice.
             */
            modifier initializer() {
                // If the contract is initializing we ignore whether _initialized is set in order to support multiple
                // inheritance patterns, but we only do this in the context of a constructor, because in other contexts the
                // contract may have been reentered.
                require(_initializing ? _isConstructor() : !_initialized, "Initializable: contract is already initialized");
                bool isTopLevelCall = !_initializing;
                if (isTopLevelCall) {
                    _initializing = true;
                    _initialized = true;
                }
                _;
                if (isTopLevelCall) {
                    _initializing = false;
                }
            }
            /**
             * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
             * {initializer} modifier, directly or indirectly.
             */
            modifier onlyInitializing() {
                require(_initializing, "Initializable: contract is not initializing");
                _;
            }
            function _isConstructor() private view returns (bool) {
                return !AddressUpgradeable.isContract(address(this));
            }
        }
        // SPDX-License-Identifier: GPL-3.0-or-later
        pragma solidity >=0.6.0;
        // helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return true/false
        library TransferHelper {
            function safeApprove(
                address token,
                address to,
                uint256 value
            ) internal {
                // bytes4(keccak256(bytes('approve(address,uint256)')));
                (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x095ea7b3, to, value));
                require(
                    success && (data.length == 0 || abi.decode(data, (bool))),
                    'TransferHelper::safeApprove: approve failed'
                );
            }
            function safeTransfer(
                address token,
                address to,
                uint256 value
            ) internal {
                // bytes4(keccak256(bytes('transfer(address,uint256)')));
                (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));
                require(
                    success && (data.length == 0 || abi.decode(data, (bool))),
                    'TransferHelper::safeTransfer: transfer failed'
                );
            }
            function safeTransferFrom(
                address token,
                address from,
                address to,
                uint256 value
            ) internal {
                // bytes4(keccak256(bytes('transferFrom(address,address,uint256)')));
                (bool success, bytes memory data) = token.call(abi.encodeWithSelector(0x23b872dd, from, to, value));
                require(
                    success && (data.length == 0 || abi.decode(data, (bool))),
                    'TransferHelper::transferFrom: transferFrom failed'
                );
            }
            function safeTransferETH(address to, uint256 value) internal {
                (bool success, ) = to.call{value: value}(new bytes(0));
                require(success, 'TransferHelper::safeTransferETH: ETH transfer failed');
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (utils/cryptography/SignatureChecker.sol)
        pragma solidity ^0.8.0;
        import "./ECDSA.sol";
        import "../Address.sol";
        import "../../interfaces/IERC1271.sol";
        /**
         * @dev Signature verification helper: Provide a single mechanism to verify both private-key (EOA) ECDSA signature and
         * ERC1271 contract signatures. Using this instead of ECDSA.recover in your contract will make them compatible with
         * smart contract wallets such as Argent and Gnosis.
         *
         * Note: unlike ECDSA signatures, contract signature's are revocable, and the outcome of this function can thus change
         * through time. It could return true at block N and false at block N+1 (or the opposite).
         *
         * _Available since v4.1._
         */
        library SignatureChecker {
            function isValidSignatureNow(
                address signer,
                bytes32 hash,
                bytes memory signature
            ) internal view returns (bool) {
                (address recovered, ECDSA.RecoverError error) = ECDSA.tryRecover(hash, signature);
                if (error == ECDSA.RecoverError.NoError && recovered == signer) {
                    return true;
                }
                (bool success, bytes memory result) = signer.staticcall(
                    abi.encodeWithSelector(IERC1271.isValidSignature.selector, hash, signature)
                );
                return (success && result.length == 32 && abi.decode(result, (bytes4)) == IERC1271.isValidSignature.selector);
            }
        }
        // SPDX-License-Identifier: GPL-3.0
        pragma solidity ^0.8.0;
        import '@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol';
        abstract contract AdminableUpgradeable is OwnableUpgradeable {
            mapping(address => bool) public isAdmin;
            event SetAdminPermission(address indexed admin, bool permission);
            modifier onlyAdmin {
                require(isAdmin[msg.sender], "Only admin can call");
                _;
            }
            modifier onlyOwnerOrAdmin {
                require((owner() == msg.sender) || isAdmin[msg.sender], "Only owner or admin can call");
                _;
            }
            function __Adminable_init() internal onlyInitializing {
                __Ownable_init();
            }
            function setAdminPermission(address _user, bool _permission) external onlyOwner {
                isAdmin[_user] = _permission;
                emit SetAdminPermission(_user, _permission);
            }
        }// SPDX-License-Identifier: GPL-3.0
        pragma solidity ^0.8.0;
        library RevertMessageParser {
            function getRevertMessage(bytes memory _data, string memory _defaultMessage) internal pure returns (string memory) {
                // If the _data length is less than 68, then the transaction failed silently (without a revert message)
                if (_data.length < 68) return _defaultMessage;
                assembly {
                    // Slice the sighash
                    _data := add(_data, 0x04)
                }
                return abi.decode(_data, (string));
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (utils/Address.sol)
        pragma solidity ^0.8.0;
        /**
         * @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
             * ====
             */
            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;
                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");
                (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");
                (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");
                (bool success, bytes memory returndata) = target.staticcall(data);
                return verifyCallResult(success, returndata, errorMessage);
            }
            /**
             * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
             * revert reason 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 {
                    // 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
                        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/cryptography/ECDSA.sol)
        pragma solidity ^0.8.0;
        import "../Strings.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 ECDSA {
            enum RecoverError {
                NoError,
                InvalidSignature,
                InvalidSignatureLength,
                InvalidSignatureS,
                InvalidSignatureV
            }
            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");
                } else if (error == RecoverError.InvalidSignatureV) {
                    revert("ECDSA: invalid signature 'v' 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) {
                // Check the signature length
                // - case 65: r,s,v signature (standard)
                // - case 64: r,vs signature (cf https://eips.ethereum.org/EIPS/eip-2098) _Available since v4.1._
                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.
                    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 if (signature.length == 64) {
                    bytes32 r;
                    bytes32 vs;
                    // ecrecover takes the signature parameters, and the only way to get them
                    // currently is to use assembly.
                    assembly {
                        r := mload(add(signature, 0x20))
                        vs := mload(add(signature, 0x40))
                    }
                    return tryRecover(hash, r, vs);
                } 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;
                uint8 v;
                assembly {
                    s := and(vs, 0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff)
                    v := add(shr(255, vs), 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 (v != 27 && v != 28) {
                    return (address(0), RecoverError.InvalidSignatureV);
                }
                // 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:\
        ", Strings.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 v4.4.1 (utils/Address.sol)
        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;
                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");
                (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");
                (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");
                (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");
                (bool success, bytes memory returndata) = target.delegatecall(data);
                return verifyCallResult(success, returndata, errorMessage);
            }
            /**
             * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
             * revert reason 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 {
                    // 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
                        assembly {
                            let returndata_size := mload(returndata)
                            revert(add(32, returndata), returndata_size)
                        }
                    } else {
                        revert(errorMessage);
                    }
                }
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (interfaces/IERC1271.sol)
        pragma solidity ^0.8.0;
        /**
         * @dev Interface of the ERC1271 standard signature validation method for
         * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
         *
         * _Available since v4.1._
         */
        interface IERC1271 {
            /**
             * @dev Should return whether the signature provided is valid for the provided data
             * @param hash      Hash of the data to be signed
             * @param signature Signature byte array associated with _data
             */
            function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (utils/Strings.sol)
        pragma solidity ^0.8.0;
        /**
         * @dev String operations.
         */
        library Strings {
            bytes16 private constant _HEX_SYMBOLS = "0123456789abcdef";
            /**
             * @dev Converts a `uint256` to its ASCII `string` decimal representation.
             */
            function toString(uint256 value) internal pure returns (string memory) {
                // Inspired by OraclizeAPI's implementation - MIT licence
                // https://github.com/oraclize/ethereum-api/blob/b42146b063c7d6ee1358846c198246239e9360e8/oraclizeAPI_0.4.25.sol
                if (value == 0) {
                    return "0";
                }
                uint256 temp = value;
                uint256 digits;
                while (temp != 0) {
                    digits++;
                    temp /= 10;
                }
                bytes memory buffer = new bytes(digits);
                while (value != 0) {
                    digits -= 1;
                    buffer[digits] = bytes1(uint8(48 + uint256(value % 10)));
                    value /= 10;
                }
                return string(buffer);
            }
            /**
             * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
             */
            function toHexString(uint256 value) internal pure returns (string memory) {
                if (value == 0) {
                    return "0x00";
                }
                uint256 temp = value;
                uint256 length = 0;
                while (temp != 0) {
                    length++;
                    temp >>= 8;
                }
                return toHexString(value, length);
            }
            /**
             * @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] = _HEX_SYMBOLS[value & 0xf];
                    value >>= 4;
                }
                require(value == 0, "Strings: hex length insufficient");
                return string(buffer);
            }
        }
        // SPDX-License-Identifier: MIT
        // OpenZeppelin Contracts v4.4.1 (access/Ownable.sol)
        pragma solidity ^0.8.0;
        import "../utils/ContextUpgradeable.sol";
        import "../proxy/utils/Initializable.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 OwnableUpgradeable is Initializable, ContextUpgradeable {
            address private _owner;
            event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
            /**
             * @dev Initializes the contract setting the deployer as the initial owner.
             */
            function __Ownable_init() internal onlyInitializing {
                __Context_init_unchained();
                __Ownable_init_unchained();
            }
            function __Ownable_init_unchained() internal onlyInitializing {
                _transferOwnership(_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 {
                _transferOwnership(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");
                _transferOwnership(newOwner);
            }
            /**
             * @dev Transfers ownership of the contract to a new account (`newOwner`).
             * Internal function without access restriction.
             */
            function _transferOwnership(address newOwner) internal virtual {
                address oldOwner = _owner;
                _owner = newOwner;
                emit OwnershipTransferred(oldOwner, newOwner);
            }
            uint256[49] private __gap;
        }
        // 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 {
                __Context_init_unchained();
            }
            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;
            }
            uint256[50] private __gap;
        }