contract Token {
    /** @return total amount of tokens
      */
    function totalSupply() view public returns (uint256 supply) {}

    /** @param _owner The address from which the balance will be retrieved
      * @return The balance
      */
    function balanceOf(address _owner) view public returns (uint256 balance) {}

    /** @notice send `_value` token to `_to` from `msg.sender`
      * @param  _to     The address of the recipient
      * @param  _value  The amount of tokens to be transferred
      * @return whether the transfer was successful or not
      */
    function transfer(address _to, uint256 _value) public {}

    /** @notice send `_value` token to `_to` from `_from` on the condition it is approved by `_from`
      * @param  _from   The address of the sender
      * @param  _to     The address of the recipient
      * @param  _value  The amount of tokens to be transferred
      * @return whether the transfer was successful or not
      */
    function transferFrom(address _from, address _to, uint256 _value)  public {}

    /** @notice `msg.sender` approves `_addr` to spend `_value` tokens
      * @param  _spender The address of the account able to transfer the tokens
      * @param  _value   The amount of wei to be approved for transfer
      * @return whether the approval was successful or not
      */
    function approve(address _spender, uint256 _value) public returns (bool success) {}

    /** @param  _owner   The address of the account owning tokens
      * @param  _spender The address of the account able to transfer the tokens
      * @return Amount of remaining tokens allowed to spend
      */
    function allowance(address _owner, address _spender) view public returns (uint256 remaining) {}

    event Transfer(address indexed _from, address indexed _to, uint256 _value);
    event Approval(address indexed _owner, address indexed _spender, uint256 _value);

    uint256 public decimals;
    string public name;
}
// Standart ERC20 token interface to interact with ERC20 token contracts
// To support badly implemented tokens (which dont return a boolean on the transfer functions)
// we have to expect a badly implemented token and then check with checkERC20TransferSuccess() whether the transfer succeeded
function totalSupply() view public returns (uint256 supply) {}

/** @return total amount of tokens
 */