code: func notifyAssociates(deviceServices []models.DeviceService, id string, action string, actionType models.ActionType) error {
  	for _, ds := range deviceServices {
  		if err := callback(ds, id, action, actionType); err != nil {
  			return err
  		}
  	}
  
  	return nil
  }
docs: // Notify associates (associated device services)
  // This function is called when an object changes in metadata