code: func SafeEncodeString(s string) string {
  	r := make([]byte, len(s))
  	for i, b := range []rune(s) {
  		r[i] = alphanums[(int(b) % len(alphanums))]
  	}
  	return string(r)
  }
docs: // SafeEncodeString encodes s using the same characters as rand.String. This reduces the chances of bad words and
  // ensures that strings generated from hash functions appear consistent throughout the API.