code: func ShuffleStrings(s []string) []string {
  	if s == nil {
  		return nil
  	}
  	shuffled := make([]string, len(s))
  	perm := utilrand.Perm(len(s))
  	for i, j := range perm {
  		shuffled[j] = s[i]
  	}
  	return shuffled
  }
docs: // ShuffleStrings copies strings from the specified slice into a copy in random
  // order. It returns a new slice.