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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 result(self):
 """ The result from realising the future If the result is not available, block until done. :return: result of the future :raises: any exception encountered during realising the future """

        if self._result is None:
            self.await_result()
        chunks, exception = self._result
        if exception is None:
            return chunks
        raise exception