code: func FromStrings(ss ...string) Labels {
  	if len(ss)%2 != 0 {
  		panic("invalid number of strings")
  	}
  	var res Labels
  	for i := 0; i < len(ss); i += 2 {
  		res = append(res, Label{Name: ss[i], Value: ss[i+1]})
  	}
  
  	sort.Sort(res)
  	return res
  }
docs: // FromStrings creates new labels from pairs of strings.