code: def start(self, future):
          
          self._check_frozen()
          self._freeze = True
          loop: asyncio.AbstractEventLoop = self.loop
  
          try:
              loop.run_until_complete(self._startup_polling())
              result = loop.run_until_complete(future)
          except (KeyboardInterrupt, SystemExit):
              result = None
              loop.stop()
          finally:
              loop.run_until_complete(self._shutdown_polling())
              log.warning("Goodbye!")
          return result
docs: Execute Future.
  
          Return the Future's result, or raise its exception.
  
          :param future:
          :return: