code: func reverse(s string) string {
  	var rs []rune
  	for len(s) > 0 {
  		r, size := utf8.DecodeLastRuneInString(s)
  		s = s[:len(s)-size]
  
  		rs = append(rs, r)
  	}
  
  	return string(rs)
  }
docs: // reverse returns the reversed form of a string