code: func staticPodManifestHealth(_ clientset.Interface) error {
  	nonExistentManifests := []string{}
  	for _, component := range constants.ControlPlaneComponents {
  		manifestFile := constants.GetStaticPodFilepath(component, constants.GetStaticPodDirectory())
  		if _, err := os.Stat(manifestFile); os.IsNotExist(err) {
  			nonExistentManifests = append(nonExistentManifests, manifestFile)
  		}
  	}
  	if len(nonExistentManifests) == 0 {
  		return nil
  	}
  	return errors.Errorf("The control plane seems to be Static Pod-hosted, but some of the manifests don't seem to exist on disk. This probably means you're running 'kubeadm upgrade' on a remote machine, which is not supported for a Static Pod-hosted cluster. Manifest files not found: %v", nonExistentManifests)
  }
docs: // staticPodManifestHealth makes sure the required static pods are presents