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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 set_topics(self, topics):
 """Set specific topics to track for metadata. Arguments: topics (list of str):
 topics to check for metadata Returns: Future: resolves after metadata request/response """

        if set(topics).difference(self._topics):
            future = self.cluster.request_update()
        else:
            future = Future().success(set(topics))
        self._topics = set(topics)
        return future