docs: private static String createPostgresTimeZone() {
      String tz = TimeZone.getDefault().getID();
      if (tz.length() <= 3 || !tz.startsWith("GMT")) {
        return tz;
      }
      char sign = tz.charAt(3);
      String start;
      switch (sign) {
        case '+':
          start = "GMT-";
          break;
        case '-':
          start = "GMT+";
          break;
        default:
          // unknown type
          return tz;
      }
  
      return start + tz.substring(4);
    }