* it.
     */
    setResult(transformResult);
  }

  /** Template method for subtypes to actually run the transform. */
  @ForOverride
  @ParametricNullness
  abstract T doTransform(F function, @ParametricNullness I result) throws Exception;

  /** Template method for subtypes to actually set the result. */
  @ForOverride
  abstract void setResult(@ParametricNullness T result);

  @Override

      return resultString + superString;
    }
    return null;
  }

  /** Template method for subtypes to actually run the fallback. */
  @ForOverride
  @ParametricNullness
  abstract T doFallback(F fallback, X throwable) throws Exception;

  /** Template method for subtypes to actually set the result. */
  @ForOverride
  abstract void setResult(@ParametricNullness T result);

  @Override

 * detailed at {@link ImmutableCollection}.
 *
 * <p><b>Warning:</b> avoid <i>direct</i> usage of {@link ImmutableMultimap} as a type (as with
 * {@link Multimap} itself). Prefer subtypes such as {@link ImmutableSetMultimap} or {@link
 * ImmutableListMultimap}, which have well-defined {@link #equals} semantics, thus avoiding a common
 * source of bugs and confusion.
 *

   * @throws NullPointerException if any of {@code elements} is null
   */
  public static <E> ImmutableSortedSet<E> copyOf(Iterable<? extends E> elements) {
    // Hack around E not being a subtype of Comparable.
    // Unsafe, see ImmutableSortedSetFauxverideShim.
    @SuppressWarnings("unchecked")
    Ordering<E> naturalOrder = (Ordering<E>) Ordering.<Comparable<?>>natural();
    return copyOf(naturalOrder, elements);

   * @throws NullPointerException if any of {@code elements} is null
   */
  public static <E> ImmutableSortedSet<E> copyOf(Iterable<? extends E> elements) {
    // Hack around E not being a subtype of Comparable.
    // Unsafe, see ImmutableSortedSetFauxverideShim.
    @SuppressWarnings("unchecked")
    Ordering<E> naturalOrder = (Ordering<E>) Ordering.<Comparable<?>>natural();
    return copyOf(naturalOrder, elements);

   * restrictive. However, the ideal signature, {@code public <S super T> S or(S)}, is not legal
   * Java. As a result, some sensible operations involving subtypes are compile errors:
   *
   * <pre>{@code
   * Optional<Integer> optionalInt = getSomeOptionalInt();
   * Number value = optionalInt.or(0.5); // error
   *

   * @throws IllegalArgumentException if any two keys are equal according to their natural ordering
   */
  public static <K, V> ImmutableSortedMap<K, V> copyOf(Map<? extends K, ? extends V> map) {
    // Hack around K not being a subtype of Comparable.
    // Unsafe, see ImmutableSortedSetFauxverideShim.
    @SuppressWarnings("unchecked")
    Ordering<K> naturalOrder = (Ordering<K>) NATURAL_ORDER;
    return copyOfInternal(map, naturalOrder);
  }

   * @throws IllegalArgumentException if any two keys are equal according to their natural ordering
   */
  public static <K, V> ImmutableSortedMap<K, V> copyOf(Map<? extends K, ? extends V> map) {
    // Hack around K not being a subtype of Comparable.
    // Unsafe, see ImmutableSortedSetFauxverideShim.
    @SuppressWarnings("unchecked")
    Ordering<K> naturalOrder = (Ordering<K>) NATURAL_ORDER;
    return copyOfInternal(map, naturalOrder);
  }

* Add 4 Japanese articles to [External Links](https://fastapi.tiangolo.com/external-links/). PR [#783](https://github.com/tiangolo/fastapi/pull/783) by [@HymanZHAN](https://github.com/HymanZHAN).
* Add support for subtypes of main types in `jsonable_encoder`, e.g. asyncpg's UUIDs. PR [#756](https://github.com/tiangolo/fastapi/pull/756) by [@RmStorm](https://github.com/RmStorm).