code: async def send_heartbeat(self, short_name):
          
  
          if short_name not in self.services:
              raise ArgumentError("Unknown service name", short_name=short_name)
  
          self.services[short_name]['state'].heartbeat()
          await self._notify_update(short_name, 'heartbeat')
docs: Post a heartbeat for a service.
  
          Args:
              short_name (string): The short name of the service to query