code: func (s *ServiceAntiAffinity) getNodeClassificationByLabels(nodes []*v1.Node) (map[string]string, []string) {
  	labeledNodes := map[string]string{}
  	nonLabeledNodes := []string{}
  	for _, node := range nodes {
  		if labels.Set(node.Labels).Has(s.label) {
  			label := labels.Set(node.Labels).Get(s.label)
  			labeledNodes[node.Name] = label
  		} else {
  			nonLabeledNodes = append(nonLabeledNodes, node.Name)
  		}
  	}
  	return labeledNodes, nonLabeledNodes
  }
docs: // Classifies nodes into ones with labels and without labels.