        // Ensure at validation that the contract has enough balance to cover the requested funds.
        // NOTE: This check is necessary to enforce that the contract will be able to transfer the remaining funds
        //       when `postOp()` is called back after the `UserOperation` has been executed.
        if (address(this).balance < withdrawAmount) {
            revert InsufficientBalance(withdrawAmount, address(this).balance);
        }
        // https://github.com/eth-infinitism/account-abstraction/blob/abff2aca61a8f0934e533d0d352978055fddbd96/contracts/core/EntryPoint.sol#L98C1-L102C10
        for (uint256 i = 0; i < opslen; i++) {
            UserOpInfo memory opInfo = opInfos[i];
            (uint256 validationData, uint256 pmValidationData) = _validatePrepayment(i, ops[i], opInfo);
            _validateAccountAndPaymasterValidationData(i, validationData, pmValidationData, address(0));
        }
        
        for (uint256 i = 0; i < opslen; i++) {
            collected += _executeUserOp(i, ops[i], opInfos[i]);
        }
        // https://github.com/code-423n4/2024-03-coinbase/blob/e0573369b865d47fed778de00a7b6df65ab1744e/src/MagicSpend/MagicSpend.sol#L160C1-L162C10
        if (withdrawable > 0) {
            SafeTransferLib.forceSafeTransferETH(account, withdrawable, SafeTransferLib.GAS_STIPEND_NO_STORAGE_WRITES);
        }
        // https://github.com/code-423n4/2024-03-coinbase/blob/e0573369b865d47fed778de00a7b6df65ab1744e/src/MagicSpend/MagicSpend.sol#L160C1-L162C10
        if (withdrawable > 0) {
            SafeTransferLib.forceSafeTransferETH(account, withdrawable, SafeTransferLib.GAS_STIPEND_NO_STORAGE_WRITES);
        }
        
        // Ensure at validation that the contract has enough balance to cover the requested funds.
        // NOTE: This check is necessary to enforce that the contract will be able to transfer the remaining funds
        //       when `postOp()` is called back after the `UserOperation` has been executed.
        if (address(this).balance < withdrawAmount) {
            revert InsufficientBalance(withdrawAmount, address(this).balance);
        }
        if (remain < withdrawAmount) {
            revert InsufficientBalance(withdrawAmount, address(this).balance);
        }
        remain -= withdrawAmount;
