code: def _remove_from_world(self):
          
          self.on_remove_from_world()
          self._extensions = {}
          self._disable_forum_observation()
          self._world = None
          self._id = None
docs: Clear all the internal data the token needed while it was part of 
          the world.
  
          Note that this method doesn't actually remove the token from the 
          world.  That's what World._remove_token() does.  This method is just 
          responsible for setting the internal state of the token being removed.