contract KeepToken is ERC20Burnable, ERC20Detailed {
    string public constant NAME = "KEEP Token";
    string public constant SYMBOL = "KEEP";
    uint8 public constant DECIMALS = 18; // The number of digits after the decimal place when displaying token values on-screen.
    uint256 public constant INITIAL_SUPPLY = 10**27; // 1 billion tokens, 18 decimal places.

    /// @dev Gives msg.sender all of existing tokens.
    constructor() public ERC20Detailed(NAME, SYMBOL, DECIMALS) {
        _mint(msg.sender, INITIAL_SUPPLY);
    }

    /// @notice Set allowance for other address and notify.
    /// Allows `_spender` to spend no more than `_value` tokens
    /// on your behalf and then ping the contract about it.
    /// @param _spender The address authorized to spend.
    /// @param _value The max amount they can spend.
    /// @param _extraData Extra information to send to the approved contract.
    function approveAndCall(
        address _spender,
        uint256 _value,
        bytes memory _extraData
    ) public returns (bool success) {
        tokenRecipient spender = tokenRecipient(_spender);
        if (approve(_spender, _value)) {
            spender.receiveApproval(
                msg.sender,
                _value,
                address(this),
                _extraData
            );
            return true;
        }
    }
}
/// @title KEEP Token
/// @dev Standard ERC20Burnable token
function approveAndCall(
        address _spender,
        uint256 _value,
        bytes memory _extraData
    ) public returns (bool success) {
        tokenRecipient spender = tokenRecipient(_spender);
        if (approve(_spender, _value)) {
            spender.receiveApproval(
                msg.sender,
                _value,
                address(this),
                _extraData
            );
            return true;
        }
    }
/// @notice Set allowance for other address and notify.
/// Allows `_spender` to spend no more than `_value` tokens
/// on your behalf and then ping the contract about it.
/// @param _spender The address authorized to spend.
/// @param _value The max amount they can spend.
/// @param _extraData Extra information to send to the approved contract.