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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 unsubscribe(self, topic):
 """Unsubscribe from messages on a given topic Args: topic (string):
 The MQTT topic to unsubscribe from """


        del self.queues[topic]

        try:
            self.client.unsubscribe(topic)
        except operationError as exc:
            raise InternalError("Could not unsubscribe from topic", topic=topic, message=exc.message)