* collection in unspecified order.
   *
   * @param collection the elements that the set should contain
   * @return a new {@code CompactHashSet} containing those elements (minus duplicates)
   */
  public static <E extends @Nullable Object> CompactHashSet<E> create(
      Collection<? extends E> collection) {
    CompactHashSet<E> set = createWithExpectedSize(collection.size());

   * collection in unspecified order.
   *
   * @param collection the elements that the set should contain
   * @return a new {@code CompactHashSet} containing those elements (minus duplicates)
   */
  public static <E extends @Nullable Object> CompactHashSet<E> create(
      Collection<? extends E> collection) {
    CompactHashSet<E> set = createWithExpectedSize(collection.size());