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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 cleanup(self):
 """Cleanup all the expired keys"""

        keys = self.client.smembers(self.keys_container)
        for key in keys:
            entry = self.client.get(key)
            if entry:
                entry = pickle.loads(entry)
                if self._is_expired(entry, self.timeout):
                    self.delete_entry(key)