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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):
 """Unsubscribe from all topics and clear all assigned partitions."""

        self._subscription.unsubscribe()
        self._coordinator.close()
        self._client.cluster.need_all_topic_metadata = False
        self._client.set_topics([])
        log.debug("Unsubscribed all topics or patterns and assigned partitions")