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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 stop(self):
 """ Stop the RpcConsumer. The RpcConsumer ordinary unregisters from the QueueConsumer when the last Rpc subclass unregisters from it. If no providers were registered, we should unregister from the QueueConsumer as soon as we're asked to stop. """

        if not self._providers_registered:
            self.queue_consumer.unregister_provider(self)
            self._unregistered_from_queue_consumer.send(True)