```\\nfunction _validateAccountPrepayment(uint256 opIndex, UserOperation calldata op, UserOpInfo memory opInfo, uint256 requiredPrefund)\\ninternal returns (uint256 gasUsedByValidateAccountPrepayment, uint256 validationData) {\\nunchecked {\\n    uint256 preGas = gasleft();\\n    MemoryUserOp memory mUserOp = opInfo.mUserOp;\\n    address sender = mUserOp.sender;\\n    _createSenderIfNeeded(opIndex, opInfo, op.initCode);\\n    address paymaster = mUserOp.paymaster;\\n    numberMarker();\\n    uint256 missingAccountFunds = 0;\\n    if (paymaster == address(0)) {\\n        uint256 bal = balanceOf(sender);\\n        missingAccountFunds = bal > requiredPrefund ? 0 : requiredPrefund - bal;\\n    }\\n    try IAccount(sender).validateUserOp{gas : mUserOp.verificationGasLimit}(op, opInfo.userOpHash, missingAccountFunds)\\n    returns (uint256 _validationData) {\\n        validationData = _validationData;\\n    } catch Error(string memory revertReason) {\\n        revert FailedOp(opIndex, string.concat("AA23 reverted: ", revertReason));\\n    } catch {\\n        revert FailedOp(opIndex, "AA23 reverted (or OOG)");\\n    }\\n    if (paymaster == address(0)) {\\n        DepositInfo storage senderInfo = deposits[sender];\\n        uint256 deposit = senderInfo.deposit;\\n        if (requiredPrefund > deposit) {\\n            revert FailedOp(opIndex, "AA21 didn't pay prefund");\\n        }\\n        senderInfo.deposit = uint112(deposit - requiredPrefund);\\n    }\\n    gasUsedByValidateAccountPrepayment = preGas - gasleft();\\n}\\n}\\n```\\n