code: func RandAlphaNumSeq(n int) string {
  	b := make([]rune, n)
  	for i := range b {
  		b[i] = alphaNum[rand.Intn(len(alphaNum))]
  	}
  	return string(b)
  }
docs: // RandAlphaNumSeq generates a random sequence of alpha-numeric characters of
  // length n.