code: func MarkAllPodsNotReady(kubeClient clientset.Interface, node *v1.Node) error {
  	nodeName := node.Name
  	klog.V(2).Infof("Update ready status of pods on node [%v]", nodeName)
  	opts := metav1.ListOptions{FieldSelector: fields.OneTermEqualSelector(api.PodHostField, nodeName).String()}
  	pods, err := kubeClient.CoreV1().Pods(metav1.NamespaceAll).List(opts)
  	if err != nil {
  		return err
  	}
  
  	errMsg := []string{}
  	for _, pod := range pods.Items {
  		// Defensive check, also needed for tests.
  		if pod.Spec.NodeName != nodeName {
  			continue
  		}
  
  		for i, cond := range pod.Status.Conditions {
  			if cond.Type == v1.PodReady {
  				pod.Status.Conditions[i].Status = v1.ConditionFalse
  				klog.V(2).Infof("Updating ready status of pod %v to false", pod.Name)
  				_, err := kubeClient.CoreV1().Pods(pod.Namespace).UpdateStatus(&pod)
  				if err != nil {
  					klog.Warningf("Failed to update status for pod %q: %v", format.Pod(&pod), err)
  					errMsg = append(errMsg, fmt.Sprintf("%v", err))
  				}
  				break
  			}
  		}
  	}
  	if len(errMsg) == 0 {
  		return nil
  	}
  	return fmt.Errorf("%v", strings.Join(errMsg, "; "))
  }
docs: // MarkAllPodsNotReady updates ready status of all pods running on
  // given node from master return true if success