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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, timeout=None):
 """Get the result of the operation, blocking if necessary. Args: timeout (int):
 How long (in seconds) to wait for the operation to complete. If None, wait indefinitely. Returns: google.protobuf.Message: The Operation's result. Raises: google.api_core.GoogleAPICallError: If the operation errors or if the timeout is reached before the operation completes. """

        self._blocking_poll(timeout=timeout)

        if self._exception is not None:
            # pylint: disable=raising-bad-type
            # Pylint doesn't recognize that this is valid in this case.
            raise self._exception

        return self._result