code: func FindLabelsInSet(labelsToKeep []string, selector labels.Set) map[string]string {
  	aL := make(map[string]string)
  	for _, l := range labelsToKeep {
  		if selector.Has(l) {
  			aL[l] = selector.Get(l)
  		}
  	}
  	return aL
  }
docs: // FindLabelsInSet gets as many key/value pairs as possible out of a label set.