code: async def message_fetcher_coroutine(self, loop):
          
          Global.LOGGER.debug('registering callbacks for message fetcher coroutine')
          self.isrunning = True
          while self.isrunning:
              loop.call_soon(self._fetch_messages)
              loop.call_soon(self._perform_system_check)
              await asyncio.sleep(Global.CONFIG_MANAGER.message_fetcher_sleep_interval)
  
          Global.LOGGER.debug('message fetcher stopped')
docs: Register callback for message fetcher coroutines