code: func IsKubeletLabel(key string) bool {
  	if kubeletLabels.Has(key) {
  		return true
  	}
  
  	namespace := getLabelNamespace(key)
  	for allowedNamespace := range kubeletLabelNamespaces {
  		if namespace == allowedNamespace || strings.HasSuffix(namespace, "."+allowedNamespace) {
  			return true
  		}
  	}
  
  	return false
  }
docs: // IsKubeletLabel returns true if the label key is one that kubelets are allowed to set on their own Node object.
  // This checks if the key is in the KubeletLabels() list, or has a namespace in the KubeletLabelNamespaces() list.