explain the paper.

  `If there's no meaning in it,' said the King, `that saves a
world of trouble, you know, as we needn't try to find any.  And
yet I don't know,' he went on, spreading out the verses on his
knee, and looking at them with one eye; `I seem to see some
meaning in them, after all.  "--SAID I COULD NOT SWIM--" you
can't swim, can you?' he added, turning to the Knave.

It also re-declares `id: int`. By doing this, we are making a **contract** with the API clients, so that they can always expect the `id` to be there and to be an `int` (it will never be `None`).

/// tip

Having the return model ensure that a value is always available and always `int` (not `None`) is very useful for the API clients, they can write much simpler code having this certainty.

            exclude_defaults=exclude_defaults,
            exclude_none=exclude_none,
        )

    def __hash__(self) -> int:
        # Each ModelField is unique for our purposes, to allow making a dict from
        # ModelField to its JSON Schema.
        return id(self)


def _has_computed_fields(field: ModelField) -> bool:
    computed_fields = field._type_adapter.core_schema.get("schema", {}).get(

 [AccessHeadersJava]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/AccessHeaders.java
 [AccessHeadersKotlin]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/kt/AccessHeaders.kt
 [PostStringJava]: https://github.com/square/okhttp/blob/master/samples/guide/src/main/java/okhttp3/recipes/PostString.java

   */
  public final <S extends @Nullable T> Equivalence<Iterable<S>> pairwise() {
    // Ideally, the returned equivalence would support Iterable<? extends T>. However,
    // the need for this is so rare that it's not worth making callers deal with the ugly wildcard.
    return new PairwiseEquivalence<>(this);
  }

  /**
   * Returns a predicate that evaluates to true if and only if the input is equivalent to {@code

      int same = 0x0; // bitset for output bits with same values
      int diff = 0x0; // bitset for output bits with different values
      int count = 0;
      // originally was 2 * Math.log(...), making it try more times to avoid flakiness issues
      int maxCount = (int) (4 * Math.log(2 * keyBits * hashBits) + 1);
      while (same != 0xffffffff || diff != 0xffffffff) {
        int key1 = rand.nextInt();

 *       unnecessary; for example, {@code copyOf(copyOf(anArrayList))} should copy the data only
 *       once. This reduces the expense of habitually making defensive copies at API boundaries.
 *       However, the precise conditions for skipping the copy operation are undefined.
 *   <li><b>Warning:</b> a view collection such as {@link ImmutableMap#keySet} or {@link

The main tasks that you can do right now are:

* [Help others with questions in GitHub](#help-others-with-questions-in-github){.internal-link target=_blank} (see the section above).
* [Review Pull Requests](#review-pull-requests){.internal-link target=_blank} (see the section above).

Those two tasks are what **consume time the most**. That's the main work of maintaining FastAPI.

       * more information, see the comments in that class.
       *
       * We already know that that's how it behaves, and subclasses of Converter can't change that
       * behavior. So there's no sense in making all subclass authors exclude the method from any
       * NullPointerTester tests that they have.
       */
      ignoredMembers.add(Converter.class.getMethod("apply", Object.class));

      int same = 0x0; // bitset for output bits with same values
      int diff = 0x0; // bitset for output bits with different values
      int count = 0;
      // originally was 2 * Math.log(...), making it try more times to avoid flakiness issues
      int maxCount = (int) (4 * Math.log(2 * keyBits * hashBits) + 1);
      while (same != 0xffffffff || diff != 0xffffffff) {
        int key1 = rand.nextInt();