code: func IsDateTime(str string) bool {
  	if len(str) < 4 {
  		return false
  	}
  	s := strings.Split(strings.ToLower(str), "t")
  	if len(s) < 2 || !IsDate(s[0]) {
  		return false
  	}
  
  	matches := rxDateTime.FindAllStringSubmatch(s[1], -1)
  	if len(matches) == 0 || len(matches[0]) == 0 {
  		return false
  	}
  	m := matches[0]
  	res := m[1] <= "23" && m[2] <= "59" && m[3] <= "59"
  	return res
  }
docs: // IsDateTime returns true when the string is a valid date-time