code: @SuppressWarnings("unchecked")
    public static <E extends Comparable<? super E>> ImmutableSortedSet<E> of(
        E e1, E e2, E e3, E e4, E e5, E e6, E... remaining) {
      Comparable[] contents = new Comparable[6 + remaining.length];
      contents[0] = e1;
      contents[1] = e2;
      contents[2] = e3;
      contents[3] = e4;
      contents[4] = e5;
      contents[5] = e6;
      System.arraycopy(remaining, 0, contents, 6, remaining.length);
      return construct(Ordering.natural(), contents.length, (E[]) contents);
    }
docs: Returns an immutable sorted set containing the given elements sorted by their natural ordering.
  When multiple elements are equivalent according to {@link Comparable#compareTo}, only the first
  one specified is included.
  
  @throws NullPointerException if any element is null
  @since 3.0 (source-compatible since 2.0)