docs: def ttl(self):
          """LeaseTimeToLive retrieves lease information.
  
          This method makes a synchronous HTTP request by default. To make an
          asynchronous HTTP request, please define a `callback` function
          to be invoked when receiving the response.
  
          :return:
          """
          result = self.client.post(self.client.get_url("/kv/lease/timetolive"),
                                    json={"ID": self.id})
          return int(result['TTL'])