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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 nack(self):
 """Decline to acknowldge the given message. This will cause the message to be re-delivered to the subscription. """

        self._request_queue.put(
            requests.NackRequest(ack_id=self._ack_id, byte_size=self.size)
        )