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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):
 """ Return the final result or raise an Exception if errors were encountered. If the final result or error has not been set yet, this method will block until it is set, or the timeout set for the request expires. Timeout is specified in the Session request execution functions. If the timeout is exceeded, an :exc:`cassandra.OperationTimedOut` will be raised. This is a client-side timeout. For more information about server-side coordinator timeouts, see :class:`.policies.RetryPolicy`. Example usage:: """

        self._event.wait()
        if self._final_result is not _NOT_SET:
            return ResultSet(self, self._final_result)
        else:
            raise self._final_exception