docs: public static <T extends Comparable<T>> RangeSet<T> unionRanges(final Iterable<Range<T>> ranges)
    {
      RangeSet<T> rangeSet = null;
      for (Range<T> range : ranges) {
        if (rangeSet == null) {
          rangeSet = TreeRangeSet.create();
        }
        rangeSet.add(range);
      }
      return rangeSet;
    }