docs: def restart_complete(self, state, new_address):
          '''
          Called when we get notified that the restart has been completed by
          some agent who has volontureed to do so.
          '''
          if state.timeout_call_id:
              state.agent.cancel_delayed_call(state.timeout_call_id)
              state.timeout_call_id = None
          return self._send_restarted_notifications(new_address)