code: func GetAttrs(obj runtime.Object) (labels.Set, fields.Set, error) {
  	namespaceObj, ok := obj.(*api.Namespace)
  	if !ok {
  		return nil, nil, fmt.Errorf("not a namespace")
  	}
  	return labels.Set(namespaceObj.Labels), NamespaceToSelectableFields(namespaceObj), nil
  }
docs: // GetAttrs returns labels and fields of a given object for filtering purposes.