def main(user_id: str):
    return user_id


# A Pydantic model
class User(BaseModel):
    id: int
    name: str
    joined: date
```

That can then be used like:

```Python
my_user: User = User(id=3, name="John Doe", joined="2018-07-19")

second_user_data = {
    "id": 4,
    "name": "Mary",
    "joined": "2018-11-30",
}

my_second_user: User = User(**second_user_data)
```

/// info

     *
     * <p>This method is used when testing iterators without a known ordering. We poll the target
     * iterator's next element and pass it to the reference iterator through this method so it can
     * return the same element. This enables the assertion to pass and the reference iterator to
     * properly update its state.
     */
    void promoteToNext(E e) {
      if (nextElements.remove(e)) {
        nextElements.push(e);

**FastAPI** knows what to do in each case and how to reuse the same object, so that all the background tasks are merged together and are run in the background afterwards:


{* ../../docs_src/background_tasks/tutorial002_an_py310.py hl[13,15,22,25] *}

   *   <li>{@code proxy.toString()} delegates to {@link AbstractInvocationHandler#toString}
   *   <li>{@code proxy.equals(argument)} returns true if:
   *       <ul>
   *         <li>{@code proxy} and {@code argument} are of the same type
   *         <li>and {@link AbstractInvocationHandler#equals} returns true for the {@link
   *             InvocationHandler} of {@code argument}
   *       </ul>

 * need for a distinct {@code ImmutableBiMultimap} type.
 *
 * <p><a id="iteration"></a>
 *
 * <p><b>Key-grouped iteration.</b> All view collections follow the same iteration order. In all
 * current implementations, the iteration order always keeps multiple entries with the same key
 * together. Any creation method that would customarily respect insertion order (such as {@link

  abstract int distinctElements();

  // Object methods

  /**
   * {@inheritDoc}
   *
   * <p>This implementation returns {@code true} if {@code object} is a multiset of the same size
   * and if, for each element, the two multisets have the same count.
   */
  @Override
  public final boolean equals(@CheckForNull Object object) {
    return Multisets.equalsImpl(this, object);
  }

  /**
   * {@inheritDoc}

So:

```Python
q: Union[str, None] = Query(default=None)
```

...makes the parameter optional, with a default value of `None`, the same as:

```Python
q: Union[str, None] = None
```

And in Python 3.10 and above:

=====================

OkHttp 4.x upgrades our implementation language from Java to Kotlin and keeps everything else the
same. We’ve chosen Kotlin because it gives us powerful new capabilities while integrating closely
with Java.

We spent a lot of time and energy on retaining strict compatibility with OkHttp 3.x. We’re even
keeping the package name the same: `okhttp3`!

There are three kinds of compatibility we’re tracking:

   *
   * <p><b>Note:</b> consider representing the collection as a {@link java.util.BitSet} instead.
   *
   * @param collection a collection of {@code Boolean} objects
   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null
   */
  public static boolean[] toArray(Collection<Boolean> collection) {

   *
   * <p><b>Note:</b> consider representing the collection as a {@link java.util.BitSet} instead.
   *
   * @param collection a collection of {@code Boolean} objects
   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null
   */
  public static boolean[] toArray(Collection<Boolean> collection) {