ETH Price: $3,861.62 (-0.90%)

Transaction Decoder

Block:
20503145 at Aug-11-2024 05:00:11 AM +UTC
Transaction Fee:
0.000075753680114376 ETH $0.29
Gas Used:
76,626 Gas / 0.988615876 Gwei

Emitted Events:

139 Proxy.0x74273f98770936abfe9aad12868d2dbe403347b74b7f3a539d0359c123d5d31c( 0x74273f98770936abfe9aad12868d2dbe403347b74b7f3a539d0359c123d5d31c, 0x000000000000000000000000642229f238fb9de03374be34b0ed8d9de80752c5, 0x0000000000000000000000000000000000000000000000000000000000000001, 000000000000000000000000000000000000000000000000020a78e993ec4d24, 000000000000000000000000000000000000000000000000020a78e993ec4d24 )
140 Proxy.0x74273f98770936abfe9aad12868d2dbe403347b74b7f3a539d0359c123d5d31c( 0x74273f98770936abfe9aad12868d2dbe403347b74b7f3a539d0359c123d5d31c, 0x0000000000000000000000005050f69a9786f081509234f1a7f4684b5e5b76c9, 0x0000000000000000000000000000000000000000000000000000000000000001, 000000000000000000000000000000000000000000000000186122045842d6b0, 000000000000000000000000000000000000000000000000186122045842d6b0 )
141 Proxy.0xbadd9d7563efca77438dc132e885aa156837e0b784469f68fbd810cbfb6cda77( 0xbadd9d7563efca77438dc132e885aa156837e0b784469f68fbd810cbfb6cda77, 0x000000000000000000000000ec8103eb573150cb92f8af612e0072843db2295f, 0x0000000000000000000000000000000000000000000000000000000000000001, 0000000000000000000000000000000000000000000000098df82f68c1fa00ef )

Account State Difference:

  Address   Before After State Difference Code
0x23B597f3...634cDf4ea 178.154460958090142915 Eth0 Eth178.154460958090142915
(Lido: Execution Layer Rewards Vault)
47.839074108157220369 Eth47.839074200108420369 Eth0.0000000919512
0x5050F69a...b5E5b76C9
(Base: Batch Sender)
548.243277268292806992 Eth550 Eth1.756722731707193008
0x642229f2...De80752c5 49.852937117552587484 Eth50 Eth0.147062882447412516
0xD46BD800...751D41Ea7
5.398970350485757459 Eth
Nonce: 241
5.398894596805643083 Eth
Nonce: 242
0.000075753680114376
0xEc8103eb...43db2295F
(Coinbase: Base Sequencer)
0.000037240085484 Eth176.250712584021021391 Eth176.250675343935537391

Execution Trace

Proxy.CALL( )
  • BalanceTracker.DELEGATECALL( )
    • ETH 0.147062882447412516 0x642229f238fb9de03374be34b0ed8d9de80752c5.CALL( )
    • ETH 1.756722731707193008 Base: Batch Sender.CALL( )
    • ETH 176.250675343935537391 Coinbase: Base Sequencer.CALL( )
      File 1 of 2: Proxy
      // SPDX-License-Identifier: MIT
      pragma solidity 0.8.15;
      /**
       * @title Proxy
       * @notice Proxy is a transparent proxy that passes through the call if the caller is the owner or
       *         if the caller is address(0), meaning that the call originated from an off-chain
       *         simulation.
       */
      contract Proxy {
          /**
           * @notice The storage slot that holds the address of the implementation.
           *         bytes32(uint256(keccak256('eip1967.proxy.implementation')) - 1)
           */
          bytes32 internal constant IMPLEMENTATION_KEY =
              0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
          /**
           * @notice The storage slot that holds the address of the owner.
           *         bytes32(uint256(keccak256('eip1967.proxy.admin')) - 1)
           */
          bytes32 internal constant OWNER_KEY =
              0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
          /**
           * @notice An event that is emitted each time the implementation is changed. This event is part
           *         of the EIP-1967 specification.
           *
           * @param implementation The address of the implementation contract
           */
          event Upgraded(address indexed implementation);
          /**
           * @notice An event that is emitted each time the owner is upgraded. This event is part of the
           *         EIP-1967 specification.
           *
           * @param previousAdmin The previous owner of the contract
           * @param newAdmin      The new owner of the contract
           */
          event AdminChanged(address previousAdmin, address newAdmin);
          /**
           * @notice A modifier that reverts if not called by the owner or by address(0) to allow
           *         eth_call to interact with this proxy without needing to use low-level storage
           *         inspection. We assume that nobody is able to trigger calls from address(0) during
           *         normal EVM execution.
           */
          modifier proxyCallIfNotAdmin() {
              if (msg.sender == _getAdmin() || msg.sender == address(0)) {
                  _;
              } else {
                  // This WILL halt the call frame on completion.
                  _doProxyCall();
              }
          }
          /**
           * @notice Sets the initial admin during contract deployment. Admin address is stored at the
           *         EIP-1967 admin storage slot so that accidental storage collision with the
           *         implementation is not possible.
           *
           * @param _admin Address of the initial contract admin. Admin as the ability to access the
           *               transparent proxy interface.
           */
          constructor(address _admin) {
              _changeAdmin(_admin);
          }
          // slither-disable-next-line locked-ether
          receive() external payable {
              // Proxy call by default.
              _doProxyCall();
          }
          // slither-disable-next-line locked-ether
          fallback() external payable {
              // Proxy call by default.
              _doProxyCall();
          }
          /**
           * @notice Set the implementation contract address. The code at the given address will execute
           *         when this contract is called.
           *
           * @param _implementation Address of the implementation contract.
           */
          function upgradeTo(address _implementation) public virtual proxyCallIfNotAdmin {
              _setImplementation(_implementation);
          }
          /**
           * @notice Set the implementation and call a function in a single transaction. Useful to ensure
           *         atomic execution of initialization-based upgrades.
           *
           * @param _implementation Address of the implementation contract.
           * @param _data           Calldata to delegatecall the new implementation with.
           */
          function upgradeToAndCall(address _implementation, bytes calldata _data)
              public
              payable
              virtual
              proxyCallIfNotAdmin
              returns (bytes memory)
          {
              _setImplementation(_implementation);
              (bool success, bytes memory returndata) = _implementation.delegatecall(_data);
              require(success, "Proxy: delegatecall to new implementation contract failed");
              return returndata;
          }
          /**
           * @notice Changes the owner of the proxy contract. Only callable by the owner.
           *
           * @param _admin New owner of the proxy contract.
           */
          function changeAdmin(address _admin) public virtual proxyCallIfNotAdmin {
              _changeAdmin(_admin);
          }
          /**
           * @notice Gets the owner of the proxy contract.
           *
           * @return Owner address.
           */
          function admin() public virtual proxyCallIfNotAdmin returns (address) {
              return _getAdmin();
          }
          /**
           * @notice Queries the implementation address.
           *
           * @return Implementation address.
           */
          function implementation() public virtual proxyCallIfNotAdmin returns (address) {
              return _getImplementation();
          }
          /**
           * @notice Sets the implementation address.
           *
           * @param _implementation New implementation address.
           */
          function _setImplementation(address _implementation) internal {
              assembly {
                  sstore(IMPLEMENTATION_KEY, _implementation)
              }
              emit Upgraded(_implementation);
          }
          /**
           * @notice Changes the owner of the proxy contract.
           *
           * @param _admin New owner of the proxy contract.
           */
          function _changeAdmin(address _admin) internal {
              address previous = _getAdmin();
              assembly {
                  sstore(OWNER_KEY, _admin)
              }
              emit AdminChanged(previous, _admin);
          }
          /**
           * @notice Performs the proxy call via a delegatecall.
           */
          function _doProxyCall() internal {
              address impl = _getImplementation();
              require(impl != address(0), "Proxy: implementation not initialized");
              assembly {
                  // Copy calldata into memory at 0x0....calldatasize.
                  calldatacopy(0x0, 0x0, calldatasize())
                  // Perform the delegatecall, make sure to pass all available gas.
                  let success := delegatecall(gas(), impl, 0x0, calldatasize(), 0x0, 0x0)
                  // Copy returndata into memory at 0x0....returndatasize. Note that this *will*
                  // overwrite the calldata that we just copied into memory but that doesn't really
                  // matter because we'll be returning in a second anyway.
                  returndatacopy(0x0, 0x0, returndatasize())
                  // Success == 0 means a revert. We'll revert too and pass the data up.
                  if iszero(success) {
                      revert(0x0, returndatasize())
                  }
                  // Otherwise we'll just return and pass the data up.
                  return(0x0, returndatasize())
              }
          }
          /**
           * @notice Queries the implementation address.
           *
           * @return Implementation address.
           */
          function _getImplementation() internal view returns (address) {
              address impl;
              assembly {
                  impl := sload(IMPLEMENTATION_KEY)
              }
              return impl;
          }
          /**
           * @notice Queries the owner of the proxy contract.
           *
           * @return Owner address.
           */
          function _getAdmin() internal view returns (address) {
              address owner;
              assembly {
                  owner := sload(OWNER_KEY)
              }
              return owner;
          }
      }
      

      File 2 of 2: BalanceTracker
      // SPDX-License-Identifier: MIT
      pragma solidity 0.8.15;
      import { Address } from "@openzeppelin/contracts/utils/Address.sol";
      import { Math } from "@openzeppelin/contracts/utils/math/Math.sol";
      import { ReentrancyGuardUpgradeable } 
          from "@openzeppelin/contracts-upgradeable/security/ReentrancyGuardUpgradeable.sol";
      import { SafeCall } from "@eth-optimism-bedrock/src/libraries/SafeCall.sol";
      /**
       * @title BalanceTracker
       * @dev Funds system addresses and sends the remaining profits to the profit wallet.
       */
      contract BalanceTracker is ReentrancyGuardUpgradeable {
          using Address for address;
          /*//////////////////////////////////////////////////////////////
                                  Constants
          //////////////////////////////////////////////////////////////*/
          /**
           * @dev The maximum number of system addresses that can be funded.
           */
          uint256 public constant MAX_SYSTEM_ADDRESS_COUNT = 20;
          
          /*//////////////////////////////////////////////////////////////
                                  Immutables
          //////////////////////////////////////////////////////////////*/
          /**
           * @dev The address of the wallet receiving profits.
           */
          address payable public immutable PROFIT_WALLET;
          
          /*//////////////////////////////////////////////////////////////
                                  VARIABLES
          //////////////////////////////////////////////////////////////*/
          /**
           * @dev The system addresses being funded.
           */
          address payable[] public systemAddresses;
          /**
           * @dev The target balances for system addresses.
           */
          uint256[] public targetBalances;
          /*//////////////////////////////////////////////////////////////
                                  Events
          //////////////////////////////////////////////////////////////*/
          /**
           * @dev Emitted when the BalanceTracker sends funds to a system address.
           * @param _systemAddress The system address being funded.
           * @param _success A boolean denoting whether a fund send occurred and its success or failure.
           * @param _balanceNeeded The amount of funds the given system address needs to reach its target balance.
           * @param _balanceSent The amount of funds sent to the system address.
           */
          event ProcessedFunds(
              address indexed _systemAddress,
              bool indexed _success,
              uint256 _balanceNeeded,
              uint256 _balanceSent
          );
          /**
           * @dev Emitted when the BalanceTracker attempts to send funds to the profit wallet.
           * @param _profitWallet The address of the profit wallet.
           * @param _success A boolean denoting the success or failure of fund send.
           * @param _balanceSent The amount of funds sent to the profit wallet.
           */
          event SentProfit(
              address indexed _profitWallet,
              bool indexed _success,
              uint256 _balanceSent
          );
          /**
           * @dev Emitted when funds are received.
           * @param _sender The address sending funds.
           * @param _amount The amount of funds received from the sender.
           */
          event ReceivedFunds(
              address indexed _sender,
              uint256 _amount
          );
          
          /*//////////////////////////////////////////////////////////////
                                  Constructor
          //////////////////////////////////////////////////////////////*/
          /**
           * @dev Constructor for the BalanceTracker contract that sets an immutable variable.
           * @param _profitWallet The address to send remaining ETH profits to.
           */
          constructor(
              address payable _profitWallet
          ) {
              require(_profitWallet != address(0), "BalanceTracker: PROFIT_WALLET cannot be address(0)");
              
              PROFIT_WALLET = _profitWallet;
              _disableInitializers();
          }
          /*//////////////////////////////////////////////////////////////
                                  External Functions
          //////////////////////////////////////////////////////////////*/
          /**
           * @dev Initializes the BalanceTracker contract.
           * @param _systemAddresses The system addresses being funded.
           * @param _targetBalances The target balances for system addresses.
           */
          function initialize(
              address payable[] memory _systemAddresses,
              uint256[] memory _targetBalances
          ) external reinitializer(2) {
              uint256 systemAddresesLength = _systemAddresses.length;
              require(systemAddresesLength > 0, 
                  "BalanceTracker: systemAddresses cannot have a length of zero");
              require(systemAddresesLength <= MAX_SYSTEM_ADDRESS_COUNT, 
                  "BalanceTracker: systemAddresses cannot have a length greater than 20");
              require(systemAddresesLength == _targetBalances.length, 
                  "BalanceTracker: systemAddresses and targetBalances length must be equal");
              for (uint256 i; i < systemAddresesLength;) {
                  require(_systemAddresses[i] != address(0), "BalanceTracker: systemAddresses cannot contain address(0)");
                  require(_targetBalances[i] > 0, "BalanceTracker: targetBalances cannot contain 0 target");
                  unchecked { i++; }
              }
              systemAddresses = _systemAddresses;
              targetBalances = _targetBalances;
              __ReentrancyGuard_init();
          }
          /**
           * @dev Funds system addresses and sends remaining profits to the profit wallet.
           * 
           */
          function processFees() external nonReentrant {
              uint256 systemAddresesLength = systemAddresses.length;
              require(systemAddresesLength > 0, 
                  "BalanceTracker: systemAddresses cannot have a length of zero");
              // Refills balances of systems addresses up to their target balances
              for (uint256 i; i < systemAddresesLength;) {
                  refillBalanceIfNeeded(systemAddresses[i], targetBalances[i]);
                  unchecked { i++; }
              }
              // Send remaining profits to profit wallet
              uint256 valueToSend = address(this).balance;
              bool success = SafeCall.send(PROFIT_WALLET, gasleft(), valueToSend);
              emit SentProfit(PROFIT_WALLET, success, valueToSend);
          }
          /**
           * @dev Fallback function to receive funds from L2 fee withdrawals and additional top up funds if
           *      L2 fees are insufficient to fund L1 system addresses.
           */
          receive() external payable {
              emit ReceivedFunds(msg.sender, msg.value);
          }
          /*//////////////////////////////////////////////////////////////
                                  Internal Functions
          //////////////////////////////////////////////////////////////*/
          /**
           * @dev Checks the balance of the target address and refills it back up to the target balance if needed.
           * @param _systemAddress The system address being funded.
           * @param _targetBalance The target balance for the system address being funded.
           */
          function refillBalanceIfNeeded(address _systemAddress, uint256 _targetBalance) internal {
               uint256 systemAddressBalance = _systemAddress.balance;
              if (systemAddressBalance >= _targetBalance) {
                  emit ProcessedFunds(_systemAddress, false, 0, 0);
                  return;
              }
              
              uint256 valueNeeded = _targetBalance - systemAddressBalance;
              uint256 balanceTrackerBalance = address(this).balance;
              uint256 valueToSend = valueNeeded > balanceTrackerBalance ? balanceTrackerBalance : valueNeeded;
              bool success = SafeCall.send(_systemAddress, gasleft(), valueToSend);
              emit ProcessedFunds(_systemAddress, success, valueNeeded, valueToSend);
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts (last updated v4.9.0) (utils/Address.sol)
      pragma solidity ^0.8.1;
      /**
       * @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
           *
           * Furthermore, `isContract` will also return true if the target contract within
           * the same transaction is already scheduled for destruction by `SELFDESTRUCT`,
           * which only has an effect at the end of a transaction.
           * ====
           *
           * [IMPORTANT]
           * ====
           * You shouldn't rely on `isContract` to protect against flash loan attacks!
           *
           * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
           * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
           * constructor.
           * ====
           */
          function isContract(address account) internal view returns (bool) {
              // This method relies on extcodesize/address.code.length, which returns 0
              // for contracts in construction, since the code is only stored at the end
              // of the constructor execution.
              return account.code.length > 0;
          }
          /**
           * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
           * `recipient`, forwarding all available gas and reverting on errors.
           *
           * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
           * of certain opcodes, possibly making contracts go over the 2300 gas limit
           * imposed by `transfer`, making them unable to receive funds via
           * `transfer`. {sendValue} removes this limitation.
           *
           * https://consensys.net/diligence/blog/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/v0.8.0/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
           */
          function sendValue(address payable recipient, uint256 amount) internal {
              require(address(this).balance >= amount, "Address: insufficient balance");
              (bool success, ) = recipient.call{value: amount}("");
              require(success, "Address: unable to send value, recipient may have reverted");
          }
          /**
           * @dev Performs a Solidity function call using a low level `call`. A
           * plain `call` is an unsafe replacement for a function call: use this
           * function instead.
           *
           * If `target` reverts with a revert reason, it is bubbled up by this
           * function (like regular Solidity function calls).
           *
           * Returns the raw returned data. To convert to the expected return value,
           * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
           *
           * Requirements:
           *
           * - `target` must be a contract.
           * - calling `target` with `data` must not revert.
           *
           * _Available since v3.1._
           */
          function functionCall(address target, bytes memory data) internal returns (bytes memory) {
              return functionCallWithValue(target, data, 0, "Address: low-level call failed");
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
           * `errorMessage` as a fallback revert reason when `target` reverts.
           *
           * _Available since v3.1._
           */
          function functionCall(
              address target,
              bytes memory data,
              string memory errorMessage
          ) internal returns (bytes memory) {
              return functionCallWithValue(target, data, 0, errorMessage);
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
           * but also transferring `value` wei to `target`.
           *
           * Requirements:
           *
           * - the calling contract must have an ETH balance of at least `value`.
           * - the called Solidity function must be `payable`.
           *
           * _Available since v3.1._
           */
          function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
              return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
          }
          /**
           * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
           * with `errorMessage` as a fallback revert reason when `target` reverts.
           *
           * _Available since v3.1._
           */
          function functionCallWithValue(
              address target,
              bytes memory data,
              uint256 value,
              string memory errorMessage
          ) internal returns (bytes memory) {
              require(address(this).balance >= value, "Address: insufficient balance for call");
              (bool success, bytes memory returndata) = target.call{value: value}(data);
              return verifyCallResultFromTarget(target, success, returndata, errorMessage);
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
           * but performing a static call.
           *
           * _Available since v3.3._
           */
          function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
              return functionStaticCall(target, data, "Address: low-level static call failed");
          }
          /**
           * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
           * but performing a static call.
           *
           * _Available since v3.3._
           */
          function functionStaticCall(
              address target,
              bytes memory data,
              string memory errorMessage
          ) internal view returns (bytes memory) {
              (bool success, bytes memory returndata) = target.staticcall(data);
              return verifyCallResultFromTarget(target, success, returndata, errorMessage);
          }
          /**
           * @dev 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) {
              (bool success, bytes memory returndata) = target.delegatecall(data);
              return verifyCallResultFromTarget(target, success, returndata, errorMessage);
          }
          /**
           * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
           * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
           *
           * _Available since v4.8._
           */
          function verifyCallResultFromTarget(
              address target,
              bool success,
              bytes memory returndata,
              string memory errorMessage
          ) internal view returns (bytes memory) {
              if (success) {
                  if (returndata.length == 0) {
                      // only check isContract if the call was successful and the return data is empty
                      // otherwise we already know that it was a contract
                      require(isContract(target), "Address: call to non-contract");
                  }
                  return returndata;
              } else {
                  _revert(returndata, errorMessage);
              }
          }
          /**
           * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
           * revert reason or using the provided one.
           *
           * _Available since v4.3._
           */
          function verifyCallResult(
              bool success,
              bytes memory returndata,
              string memory errorMessage
          ) internal pure returns (bytes memory) {
              if (success) {
                  return returndata;
              } else {
                  _revert(returndata, errorMessage);
              }
          }
          function _revert(bytes memory returndata, string memory errorMessage) private pure {
              // Look for revert reason and bubble it up if present
              if (returndata.length > 0) {
                  // The easiest way to bubble the revert reason is using memory via assembly
                  /// @solidity memory-safe-assembly
                  assembly {
                      let returndata_size := mload(returndata)
                      revert(add(32, returndata), returndata_size)
                  }
              } else {
                  revert(errorMessage);
              }
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts (last updated v4.9.0) (utils/math/Math.sol)
      pragma solidity ^0.8.0;
      /**
       * @dev Standard math utilities missing in the Solidity language.
       */
      library Math {
          enum Rounding {
              Down, // Toward negative infinity
              Up, // Toward infinity
              Zero // Toward zero
          }
          /**
           * @dev Returns the largest of two numbers.
           */
          function max(uint256 a, uint256 b) internal pure returns (uint256) {
              return a > b ? a : b;
          }
          /**
           * @dev Returns the smallest of two numbers.
           */
          function min(uint256 a, uint256 b) internal pure returns (uint256) {
              return a < b ? a : b;
          }
          /**
           * @dev Returns the average of two numbers. The result is rounded towards
           * zero.
           */
          function average(uint256 a, uint256 b) internal pure returns (uint256) {
              // (a + b) / 2 can overflow.
              return (a & b) + (a ^ b) / 2;
          }
          /**
           * @dev Returns the ceiling of the division of two numbers.
           *
           * This differs from standard division with `/` in that it rounds up instead
           * of rounding down.
           */
          function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
              // (a + b - 1) / b can overflow on addition, so we distribute.
              return a == 0 ? 0 : (a - 1) / b + 1;
          }
          /**
           * @notice Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or denominator == 0
           * @dev Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv)
           * with further edits by Uniswap Labs also under MIT license.
           */
          function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
              unchecked {
                  // 512-bit multiply [prod1 prod0] = x * y. Compute the product mod 2^256 and mod 2^256 - 1, then use
                  // use the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
                  // variables such that product = prod1 * 2^256 + prod0.
                  uint256 prod0; // Least significant 256 bits of the product
                  uint256 prod1; // Most significant 256 bits of the product
                  assembly {
                      let mm := mulmod(x, y, not(0))
                      prod0 := mul(x, y)
                      prod1 := sub(sub(mm, prod0), lt(mm, prod0))
                  }
                  // Handle non-overflow cases, 256 by 256 division.
                  if (prod1 == 0) {
                      // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                      // The surrounding unchecked block does not change this fact.
                      // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                      return prod0 / denominator;
                  }
                  // Make sure the result is less than 2^256. Also prevents denominator == 0.
                  require(denominator > prod1, "Math: mulDiv overflow");
                  ///////////////////////////////////////////////
                  // 512 by 256 division.
                  ///////////////////////////////////////////////
                  // Make division exact by subtracting the remainder from [prod1 prod0].
                  uint256 remainder;
                  assembly {
                      // Compute remainder using mulmod.
                      remainder := mulmod(x, y, denominator)
                      // Subtract 256 bit number from 512 bit number.
                      prod1 := sub(prod1, gt(remainder, prod0))
                      prod0 := sub(prod0, remainder)
                  }
                  // Factor powers of two out of denominator and compute largest power of two divisor of denominator. Always >= 1.
                  // See https://cs.stackexchange.com/q/138556/92363.
                  // Does not overflow because the denominator cannot be zero at this stage in the function.
                  uint256 twos = denominator & (~denominator + 1);
                  assembly {
                      // Divide denominator by twos.
                      denominator := div(denominator, twos)
                      // Divide [prod1 prod0] by twos.
                      prod0 := div(prod0, twos)
                      // Flip twos such that it is 2^256 / twos. If twos is zero, then it becomes one.
                      twos := add(div(sub(0, twos), twos), 1)
                  }
                  // Shift in bits from prod1 into prod0.
                  prod0 |= prod1 * twos;
                  // Invert denominator mod 2^256. Now that denominator is an odd number, it has an inverse modulo 2^256 such
                  // that denominator * inv = 1 mod 2^256. Compute the inverse by starting with a seed that is correct for
                  // four bits. That is, denominator * inv = 1 mod 2^4.
                  uint256 inverse = (3 * denominator) ^ 2;
                  // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also works
                  // in modular arithmetic, doubling the correct bits in each step.
                  inverse *= 2 - denominator * inverse; // inverse mod 2^8
                  inverse *= 2 - denominator * inverse; // inverse mod 2^16
                  inverse *= 2 - denominator * inverse; // inverse mod 2^32
                  inverse *= 2 - denominator * inverse; // inverse mod 2^64
                  inverse *= 2 - denominator * inverse; // inverse mod 2^128
                  inverse *= 2 - denominator * inverse; // inverse mod 2^256
                  // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                  // This will give us the correct result modulo 2^256. Since the preconditions guarantee that the outcome is
                  // less than 2^256, this is the final result. We don't need to compute the high bits of the result and prod1
                  // is no longer required.
                  result = prod0 * inverse;
                  return result;
              }
          }
          /**
           * @notice Calculates x * y / denominator with full precision, following the selected rounding direction.
           */
          function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
              uint256 result = mulDiv(x, y, denominator);
              if (rounding == Rounding.Up && mulmod(x, y, denominator) > 0) {
                  result += 1;
              }
              return result;
          }
          /**
           * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded down.
           *
           * Inspired by Henry S. Warren, Jr.'s "Hacker's Delight" (Chapter 11).
           */
          function sqrt(uint256 a) internal pure returns (uint256) {
              if (a == 0) {
                  return 0;
              }
              // For our first guess, we get the biggest power of 2 which is smaller than the square root of the target.
              //
              // We know that the "msb" (most significant bit) of our target number `a` is a power of 2 such that we have
              // `msb(a) <= a < 2*msb(a)`. This value can be written `msb(a)=2**k` with `k=log2(a)`.
              //
              // This can be rewritten `2**log2(a) <= a < 2**(log2(a) + 1)`
              // → `sqrt(2**k) <= sqrt(a) < sqrt(2**(k+1))`
              // → `2**(k/2) <= sqrt(a) < 2**((k+1)/2) <= 2**(k/2 + 1)`
              //
              // Consequently, `2**(log2(a) / 2)` is a good first approximation of `sqrt(a)` with at least 1 correct bit.
              uint256 result = 1 << (log2(a) >> 1);
              // At this point `result` is an estimation with one bit of precision. We know the true value is a uint128,
              // since it is the square root of a uint256. Newton's method converges quadratically (precision doubles at
              // every iteration). We thus need at most 7 iteration to turn our partial result with one bit of precision
              // into the expected uint128 result.
              unchecked {
                  result = (result + a / result) >> 1;
                  result = (result + a / result) >> 1;
                  result = (result + a / result) >> 1;
                  result = (result + a / result) >> 1;
                  result = (result + a / result) >> 1;
                  result = (result + a / result) >> 1;
                  result = (result + a / result) >> 1;
                  return min(result, a / result);
              }
          }
          /**
           * @notice Calculates sqrt(a), following the selected rounding direction.
           */
          function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
              unchecked {
                  uint256 result = sqrt(a);
                  return result + (rounding == Rounding.Up && result * result < a ? 1 : 0);
              }
          }
          /**
           * @dev Return the log in base 2, rounded down, of a positive value.
           * Returns 0 if given 0.
           */
          function log2(uint256 value) internal pure returns (uint256) {
              uint256 result = 0;
              unchecked {
                  if (value >> 128 > 0) {
                      value >>= 128;
                      result += 128;
                  }
                  if (value >> 64 > 0) {
                      value >>= 64;
                      result += 64;
                  }
                  if (value >> 32 > 0) {
                      value >>= 32;
                      result += 32;
                  }
                  if (value >> 16 > 0) {
                      value >>= 16;
                      result += 16;
                  }
                  if (value >> 8 > 0) {
                      value >>= 8;
                      result += 8;
                  }
                  if (value >> 4 > 0) {
                      value >>= 4;
                      result += 4;
                  }
                  if (value >> 2 > 0) {
                      value >>= 2;
                      result += 2;
                  }
                  if (value >> 1 > 0) {
                      result += 1;
                  }
              }
              return result;
          }
          /**
           * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
           * Returns 0 if given 0.
           */
          function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
              unchecked {
                  uint256 result = log2(value);
                  return result + (rounding == Rounding.Up && 1 << result < value ? 1 : 0);
              }
          }
          /**
           * @dev Return the log in base 10, rounded down, of a positive value.
           * Returns 0 if given 0.
           */
          function log10(uint256 value) internal pure returns (uint256) {
              uint256 result = 0;
              unchecked {
                  if (value >= 10 ** 64) {
                      value /= 10 ** 64;
                      result += 64;
                  }
                  if (value >= 10 ** 32) {
                      value /= 10 ** 32;
                      result += 32;
                  }
                  if (value >= 10 ** 16) {
                      value /= 10 ** 16;
                      result += 16;
                  }
                  if (value >= 10 ** 8) {
                      value /= 10 ** 8;
                      result += 8;
                  }
                  if (value >= 10 ** 4) {
                      value /= 10 ** 4;
                      result += 4;
                  }
                  if (value >= 10 ** 2) {
                      value /= 10 ** 2;
                      result += 2;
                  }
                  if (value >= 10 ** 1) {
                      result += 1;
                  }
              }
              return result;
          }
          /**
           * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
           * Returns 0 if given 0.
           */
          function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
              unchecked {
                  uint256 result = log10(value);
                  return result + (rounding == Rounding.Up && 10 ** result < value ? 1 : 0);
              }
          }
          /**
           * @dev Return the log in base 256, rounded down, of a positive value.
           * Returns 0 if given 0.
           *
           * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
           */
          function log256(uint256 value) internal pure returns (uint256) {
              uint256 result = 0;
              unchecked {
                  if (value >> 128 > 0) {
                      value >>= 128;
                      result += 16;
                  }
                  if (value >> 64 > 0) {
                      value >>= 64;
                      result += 8;
                  }
                  if (value >> 32 > 0) {
                      value >>= 32;
                      result += 4;
                  }
                  if (value >> 16 > 0) {
                      value >>= 16;
                      result += 2;
                  }
                  if (value >> 8 > 0) {
                      result += 1;
                  }
              }
              return result;
          }
          /**
           * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
           * Returns 0 if given 0.
           */
          function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
              unchecked {
                  uint256 result = log256(value);
                  return result + (rounding == Rounding.Up && 1 << (result << 3) < value ? 1 : 0);
              }
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts v4.4.1 (security/ReentrancyGuard.sol)
      pragma solidity ^0.8.0;
      import "../proxy/utils/Initializable.sol";
      /**
       * @dev Contract module that helps prevent reentrant calls to a function.
       *
       * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
       * available, which can be applied to functions to make sure there are no nested
       * (reentrant) calls to them.
       *
       * Note that because there is a single `nonReentrant` guard, functions marked as
       * `nonReentrant` may not call one another. This can be worked around by making
       * those functions `private`, and then adding `external` `nonReentrant` entry
       * points to them.
       *
       * TIP: If you would like to learn more about reentrancy and alternative ways
       * to protect against it, check out our blog post
       * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
       */
      abstract contract ReentrancyGuardUpgradeable is Initializable {
          // Booleans are more expensive than uint256 or any type that takes up a full
          // word because each write operation emits an extra SLOAD to first read the
          // slot's contents, replace the bits taken up by the boolean, and then write
          // back. This is the compiler's defense against contract upgrades and
          // pointer aliasing, and it cannot be disabled.
          // The values being non-zero value makes deployment a bit more expensive,
          // but in exchange the refund on every call to nonReentrant will be lower in
          // amount. Since refunds are capped to a percentage of the total
          // transaction's gas, it is best to keep them low in cases like this one, to
          // increase the likelihood of the full refund coming into effect.
          uint256 private constant _NOT_ENTERED = 1;
          uint256 private constant _ENTERED = 2;
          uint256 private _status;
          function __ReentrancyGuard_init() internal onlyInitializing {
              __ReentrancyGuard_init_unchained();
          }
          function __ReentrancyGuard_init_unchained() internal onlyInitializing {
              _status = _NOT_ENTERED;
          }
          /**
           * @dev Prevents a contract from calling itself, directly or indirectly.
           * Calling a `nonReentrant` function from another `nonReentrant`
           * function is not supported. It is possible to prevent this from happening
           * by making the `nonReentrant` function external, and making it call a
           * `private` function that does the actual work.
           */
          modifier nonReentrant() {
              // On the first call to nonReentrant, _notEntered will be true
              require(_status != _ENTERED, "ReentrancyGuard: reentrant call");
              // Any calls to nonReentrant after this point will fail
              _status = _ENTERED;
              _;
              // By storing the original value once again, a refund is triggered (see
              // https://eips.ethereum.org/EIPS/eip-2200)
              _status = _NOT_ENTERED;
          }
          /**
           * @dev This empty reserved space is put in place to allow future versions to add new
           * variables without shifting down storage in the inheritance chain.
           * See https://docs.openzeppelin.com/contracts/4.x/upgradeable#storage_gaps
           */
          uint256[49] private __gap;
      }
      // SPDX-License-Identifier: MIT
      pragma solidity 0.8.15;
      /// @title SafeCall
      /// @notice Perform low level safe calls
      library SafeCall {
          /// @notice Performs a low level call without copying any returndata.
          /// @dev Passes no calldata to the call context.
          /// @param _target   Address to call
          /// @param _gas      Amount of gas to pass to the call
          /// @param _value    Amount of value to pass to the call
          function send(address _target, uint256 _gas, uint256 _value) internal returns (bool) {
              bool _success;
              assembly {
                  _success :=
                      call(
                          _gas, // gas
                          _target, // recipient
                          _value, // ether value
                          0, // inloc
                          0, // inlen
                          0, // outloc
                          0 // outlen
                      )
              }
              return _success;
          }
          /// @notice Perform a low level call without copying any returndata
          /// @param _target   Address to call
          /// @param _gas      Amount of gas to pass to the call
          /// @param _value    Amount of value to pass to the call
          /// @param _calldata Calldata to pass to the call
          function call(address _target, uint256 _gas, uint256 _value, bytes memory _calldata) internal returns (bool) {
              bool _success;
              assembly {
                  _success :=
                      call(
                          _gas, // gas
                          _target, // recipient
                          _value, // ether value
                          add(_calldata, 32), // inloc
                          mload(_calldata), // inlen
                          0, // outloc
                          0 // outlen
                      )
              }
              return _success;
          }
          /// @notice Helper function to determine if there is sufficient gas remaining within the context
          ///         to guarantee that the minimum gas requirement for a call will be met as well as
          ///         optionally reserving a specified amount of gas for after the call has concluded.
          /// @param _minGas      The minimum amount of gas that may be passed to the target context.
          /// @param _reservedGas Optional amount of gas to reserve for the caller after the execution
          ///                     of the target context.
          /// @return `true` if there is enough gas remaining to safely supply `_minGas` to the target
          ///         context as well as reserve `_reservedGas` for the caller after the execution of
          ///         the target context.
          /// @dev !!!!! FOOTGUN ALERT !!!!!
          ///      1.) The 40_000 base buffer is to account for the worst case of the dynamic cost of the
          ///          `CALL` opcode's `address_access_cost`, `positive_value_cost`, and
          ///          `value_to_empty_account_cost` factors with an added buffer of 5,700 gas. It is
          ///          still possible to self-rekt by initiating a withdrawal with a minimum gas limit
          ///          that does not account for the `memory_expansion_cost` & `code_execution_cost`
          ///          factors of the dynamic cost of the `CALL` opcode.
          ///      2.) This function should *directly* precede the external call if possible. There is an
          ///          added buffer to account for gas consumed between this check and the call, but it
          ///          is only 5,700 gas.
          ///      3.) Because EIP-150 ensures that a maximum of 63/64ths of the remaining gas in the call
          ///          frame may be passed to a subcontext, we need to ensure that the gas will not be
          ///          truncated.
          ///      4.) Use wisely. This function is not a silver bullet.
          function hasMinGas(uint256 _minGas, uint256 _reservedGas) internal view returns (bool) {
              bool _hasMinGas;
              assembly {
                  // Equation: gas × 63 ≥ minGas × 64 + 63(40_000 + reservedGas)
                  _hasMinGas := iszero(lt(mul(gas(), 63), add(mul(_minGas, 64), mul(add(40000, _reservedGas), 63))))
              }
              return _hasMinGas;
          }
          /// @notice Perform a low level call without copying any returndata. This function
          ///         will revert if the call cannot be performed with the specified minimum
          ///         gas.
          /// @param _target   Address to call
          /// @param _minGas   The minimum amount of gas that may be passed to the call
          /// @param _value    Amount of value to pass to the call
          /// @param _calldata Calldata to pass to the call
          function callWithMinGas(
              address _target,
              uint256 _minGas,
              uint256 _value,
              bytes memory _calldata
          )
              internal
              returns (bool)
          {
              bool _success;
              bool _hasMinGas = hasMinGas(_minGas, 0);
              assembly {
                  // Assertion: gasleft() >= (_minGas * 64) / 63 + 40_000
                  if iszero(_hasMinGas) {
                      // Store the "Error(string)" selector in scratch space.
                      mstore(0, 0x08c379a0)
                      // Store the pointer to the string length in scratch space.
                      mstore(32, 32)
                      // Store the string.
                      //
                      // SAFETY:
                      // - We pad the beginning of the string with two zero bytes as well as the
                      // length (24) to ensure that we override the free memory pointer at offset
                      // 0x40. This is necessary because the free memory pointer is likely to
                      // be greater than 1 byte when this function is called, but it is incredibly
                      // unlikely that it will be greater than 3 bytes. As for the data within
                      // 0x60, it is ensured that it is 0 due to 0x60 being the zero offset.
                      // - It's fine to clobber the free memory pointer, we're reverting.
                      mstore(88, 0x0000185361666543616c6c3a204e6f7420656e6f75676820676173)
                      // Revert with 'Error("SafeCall: Not enough gas")'
                      revert(28, 100)
                  }
                  // The call will be supplied at least ((_minGas * 64) / 63) gas due to the
                  // above assertion. This ensures that, in all circumstances (except for when the
                  // `_minGas` does not account for the `memory_expansion_cost` and `code_execution_cost`
                  // factors of the dynamic cost of the `CALL` opcode), the call will receive at least
                  // the minimum amount of gas specified.
                  _success :=
                      call(
                          gas(), // gas
                          _target, // recipient
                          _value, // ether value
                          add(_calldata, 32), // inloc
                          mload(_calldata), // inlen
                          0x00, // outloc
                          0x00 // outlen
                      )
              }
              return _success;
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts (last updated v4.7.0) (proxy/utils/Initializable.sol)
      pragma solidity ^0.8.2;
      import "../../utils/AddressUpgradeable.sol";
      /**
       * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
       * behind a proxy. Since proxied contracts do not make use of a constructor, it's common to move constructor logic to an
       * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
       * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
       *
       * The initialization functions use a version number. Once a version number is used, it is consumed and cannot be
       * reused. This mechanism prevents re-execution of each "step" but allows the creation of new initialization steps in
       * case an upgrade adds a module that needs to be initialized.
       *
       * For example:
       *
       * [.hljs-theme-light.nopadding]
       * ```
       * contract MyToken is ERC20Upgradeable {
       *     function initialize() initializer public {
       *         __ERC20_init("MyToken", "MTK");
       *     }
       * }
       * contract MyTokenV2 is MyToken, ERC20PermitUpgradeable {
       *     function initializeV2() reinitializer(2) public {
       *         __ERC20Permit_init("MyToken");
       *     }
       * }
       * ```
       *
       * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
       * possible by providing the encoded function call as the `_data` argument to {ERC1967Proxy-constructor}.
       *
       * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
       * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
       *
       * [CAUTION]
       * ====
       * Avoid leaving a contract uninitialized.
       *
       * An uninitialized contract can be taken over by an attacker. This applies to both a proxy and its implementation
       * contract, which may impact the proxy. To prevent the implementation contract from being used, you should invoke
       * the {_disableInitializers} function in the constructor to automatically lock it when it is deployed:
       *
       * [.hljs-theme-light.nopadding]
       * ```
       * /// @custom:oz-upgrades-unsafe-allow constructor
       * constructor() {
       *     _disableInitializers();
       * }
       * ```
       * ====
       */
      abstract contract Initializable {
          /**
           * @dev Indicates that the contract has been initialized.
           * @custom:oz-retyped-from bool
           */
          uint8 private _initialized;
          /**
           * @dev Indicates that the contract is in the process of being initialized.
           */
          bool private _initializing;
          /**
           * @dev Triggered when the contract has been initialized or reinitialized.
           */
          event Initialized(uint8 version);
          /**
           * @dev A modifier that defines a protected initializer function that can be invoked at most once. In its scope,
           * `onlyInitializing` functions can be used to initialize parent contracts. Equivalent to `reinitializer(1)`.
           */
          modifier initializer() {
              bool isTopLevelCall = !_initializing;
              require(
                  (isTopLevelCall && _initialized < 1) || (!AddressUpgradeable.isContract(address(this)) && _initialized == 1),
                  "Initializable: contract is already initialized"
              );
              _initialized = 1;
              if (isTopLevelCall) {
                  _initializing = true;
              }
              _;
              if (isTopLevelCall) {
                  _initializing = false;
                  emit Initialized(1);
              }
          }
          /**
           * @dev A modifier that defines a protected reinitializer function that can be invoked at most once, and only if the
           * contract hasn't been initialized to a greater version before. In its scope, `onlyInitializing` functions can be
           * used to initialize parent contracts.
           *
           * `initializer` is equivalent to `reinitializer(1)`, so a reinitializer may be used after the original
           * initialization step. This is essential to configure modules that are added through upgrades and that require
           * initialization.
           *
           * Note that versions can jump in increments greater than 1; this implies that if multiple reinitializers coexist in
           * a contract, executing them in the right order is up to the developer or operator.
           */
          modifier reinitializer(uint8 version) {
              require(!_initializing && _initialized < version, "Initializable: contract is already initialized");
              _initialized = version;
              _initializing = true;
              _;
              _initializing = false;
              emit Initialized(version);
          }
          /**
           * @dev Modifier to protect an initialization function so that it can only be invoked by functions with the
           * {initializer} and {reinitializer} modifiers, directly or indirectly.
           */
          modifier onlyInitializing() {
              require(_initializing, "Initializable: contract is not initializing");
              _;
          }
          /**
           * @dev Locks the contract, preventing any future reinitialization. This cannot be part of an initializer call.
           * Calling this in the constructor of a contract will prevent that contract from being initialized or reinitialized
           * to any version. It is recommended to use this to lock implementation contracts that are designed to be called
           * through proxies.
           */
          function _disableInitializers() internal virtual {
              require(!_initializing, "Initializable: contract is initializing");
              if (_initialized < type(uint8).max) {
                  _initialized = type(uint8).max;
                  emit Initialized(type(uint8).max);
              }
          }
      }
      // SPDX-License-Identifier: MIT
      // OpenZeppelin Contracts (last updated v4.7.0) (utils/Address.sol)
      pragma solidity ^0.8.1;
      /**
       * @dev Collection of functions related to the address type
       */
      library AddressUpgradeable {
          /**
           * @dev Returns true if `account` is a contract.
           *
           * [IMPORTANT]
           * ====
           * It is unsafe to assume that an address for which this function returns
           * false is an externally-owned account (EOA) and not a contract.
           *
           * Among others, `isContract` will return false for the following
           * types of addresses:
           *
           *  - an externally-owned account
           *  - a contract in construction
           *  - an address where a contract will be created
           *  - an address where a contract lived, but was destroyed
           * ====
           *
           * [IMPORTANT]
           * ====
           * You shouldn't rely on `isContract` to protect against flash loan attacks!
           *
           * Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
           * like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
           * constructor.
           * ====
           */
          function isContract(address account) internal view returns (bool) {
              // This method relies on extcodesize/address.code.length, which returns 0
              // for contracts in construction, since the code is only stored at the end
              // of the constructor execution.
              return account.code.length > 0;
          }
          /**
           * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
           * `recipient`, forwarding all available gas and reverting on errors.
           *
           * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
           * of certain opcodes, possibly making contracts go over the 2300 gas limit
           * imposed by `transfer`, making them unable to receive funds via
           * `transfer`. {sendValue} removes this limitation.
           *
           * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
           *
           * IMPORTANT: because control is transferred to `recipient`, care must be
           * taken to not create reentrancy vulnerabilities. Consider using
           * {ReentrancyGuard} or the
           * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
           */
          function sendValue(address payable recipient, uint256 amount) internal {
              require(address(this).balance >= amount, "Address: insufficient balance");
              (bool success, ) = recipient.call{value: amount}("");
              require(success, "Address: unable to send value, recipient may have reverted");
          }
          /**
           * @dev Performs a Solidity function call using a low level `call`. A
           * plain `call` is an unsafe replacement for a function call: use this
           * function instead.
           *
           * If `target` reverts with a revert reason, it is bubbled up by this
           * function (like regular Solidity function calls).
           *
           * Returns the raw returned data. To convert to the expected return value,
           * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
           *
           * Requirements:
           *
           * - `target` must be a contract.
           * - calling `target` with `data` must not revert.
           *
           * _Available since v3.1._
           */
          function functionCall(address target, bytes memory data) internal returns (bytes memory) {
              return 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
                      /// @solidity memory-safe-assembly
                      assembly {
                          let returndata_size := mload(returndata)
                          revert(add(32, returndata), returndata_size)
                      }
                  } else {
                      revert(errorMessage);
                  }
              }
          }
      }