code: private @Nullable String stripDefault(List<OptionElement> options) {
      String result = null;
      for (Iterator<OptionElement> i = options.iterator(); i.hasNext();) {
        OptionElement option = i.next();
        if (option.getName().equals("default")) {
          i.remove();
          result = String.valueOf(option.getValue()); // Defaults aren't options!
        }
      }
      return result;
    }
docs: Defaults aren't options. This finds an option named "default", removes, and returns it. Returns
  null if no default option is present.