code: def handle_subscribed_event(self, event_obj, event_name):
          
          handler, args = self.handlers[event_name]
          self.executor.submit(handler, event_obj, *args)
docs: Execute the registered handler of an event.
  
          Retrieve the handler and its arguments, and execute the handler in a
              new thread.
  
          Args:
              event_obj: Json object of the event.
              event_name: Name of the event to call handler for.