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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def append(self, result):
 """ Append a new Result to the list. :param result: Result to append :return: Nothing :raises: TypeError if result is not Result or ResultList """

        if isinstance(result, Result):
            self.data.append(result)
        elif isinstance(result, ResultList):
            self.data += result.data
        else:
            raise TypeError('unknown result type')