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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 keys(self):
 """Get the keys associated with this lease. :return: """

        result = self.client.post(self.client.get_url("/kv/lease/timetolive"),
                                  json={"ID": self.id,
                                        "keys": True})
        keys = result['keys'] if 'keys' in result else []
        return [_decode(key) for key in keys]