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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 consume(self, callback, queue):
 """ Register a new consumer. This consumer will be configured for every protocol this factory produces so it will be reconfigured on network failures. If a connection is already active, the consumer will be added to it. Args: callback (callable):
 The callback to invoke when a message arrives. queue (str):
 The name of the queue to consume from. """

        self.consumers[queue] = callback
        if self._client_ready.called:
            return self.client.consume(callback, queue)