code: func AddOrUpdateLabelsOnNode(kubeClient clientset.Interface, labelsToUpdate map[string]string, node *v1.Node) bool {
  	err := controller.AddOrUpdateLabelsOnNode(kubeClient, node.Name, labelsToUpdate)
  	if err != nil {
  		utilruntime.HandleError(
  			fmt.Errorf(
  				"unable to update labels %+v for Node %q: %v",
  				labelsToUpdate,
  				node.Name,
  				err))
  		return false
  	}
  	klog.V(4).Infof("Updated labels %+v to Node %v", labelsToUpdate, node.Name)
  	return true
  }
docs: // AddOrUpdateLabelsOnNode updates the labels on the node and returns true on
  // success and false on failure.