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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 pauseProducing(self):
 """ Pause the reception of messages by canceling all existing consumers. This does not disconnect from the server. Message reception can be resumed with :meth:`resumeProducing`. Returns: Deferred: fired when the production is paused. """

        if not self._running:
            return
        # Exit the read loop and cancel the consumer on the server.
        self._running = False
        for consumer in self._consumers.values():
            yield consumer.channel.basic_cancel(consumer_tag=consumer.tag)
        _legacy_twisted_log.msg("Paused retrieval of messages for the server queue")