Inklusive externer Bibliotheken, die auf Pydantic basieren, wie <abbr title="Object-Relational Mapper (Abbildung von Objekten auf relationale Strukturen)">ORM</abbr>s, <abbr title="Object-Document Mapper (Abbildung von Objekten auf nicht-relationale Strukturen)">ODM</abbr>s für Datenbanken.

    sponsors = []
    for key in keys:
        sponsor_group = []
        for login, sponsor in tiers[key].items():
            sponsor_group.append(
                {"login": login, "avatarUrl": sponsor.avatarUrl, "url": sponsor.url}
            )
        sponsors.append(sponsor_group)

    people = {
        "maintainers": maintainers,
        "experts": experts,
        "last_month_experts": last_month_experts,

```Python
    first_name="john", last_name="doe"
```

It's a different thing.

We are using colons (`:`), not equals (`=`).

And adding type hints normally doesn't change what happens from what would happen without them.

But now, imagine you are again in the middle of creating that function, but with type hints.

At the same point, you try to trigger the autocomplete with `Ctrl+Space` and you see:

        settings=settings, discussion_number=discussion_number
    )

    while discussion_edges:
        for discussion_edge in discussion_edges:
            comment_nodes.append(discussion_edge.node)
        last_edge = discussion_edges[-1]
        discussion_edges = get_graphql_translation_discussion_comments_edges(
            settings=settings,
            discussion_number=discussion_number,

    caught = []

    @websocket_middleware
    async def catcher(websocket, call_next):
        try:
            return await call_next()
        except Exception as e:  # pragma: no cover
            caught.append(e)
            raise

    myapp = make_app(middleware=[Middleware(catcher)])

    client = TestClient(myapp)
    with pytest.raises(WebSocketDisconnect) as e:

**FastAPI**は<a href="https://docs.pydantic.dev/" class="external-link" target="_blank"><strong>Pydantic </strong></a>と完全に互換性があります（そしてベースになっています）。したがって、追加のPydanticコードがあれば、それも機能します。

データベースのために<abbr title = "Object-Relational Mapper">ORM</abbr>sや、<abbr title = "Object-Document Mapper">ODM</abbr>sなどの、Pydanticに基づく外部ライブラリを備えています。

これは、すべてが自動的に検証されるため、多くの場合、リクエストから取得したオブジェクトを**データベースに直接**渡すことができるということを意味しています。

同じことがその逆にも当てはまり、多くの場合、データベースから取得したオブジェクトを**クライアントに直接**渡すことができます。

Sie sehen eine einfache Seite wie:

<img src="/img/tutorial/websockets/image01.png">

Sie können Nachrichten in das Eingabefeld tippen und absenden:

<img src="/img/tutorial/websockets/image02.png">

Und Ihre **FastAPI**-Anwendung mit WebSockets antwortet:

<img src="/img/tutorial/websockets/image03.png">

{!../../../docs_src/events/tutorial002.py!}
```

Hier schreibt die `shutdown`-Eventhandler-Funktion eine Textzeile `"Application shutdown"` in eine Datei `log.txt`.

!!! info
    In der Funktion `open()` bedeutet `mode="a"` „append“ („anhängen“), sodass die Zeile nach dem, was sich in dieser Datei befindet, hinzugefügt wird, ohne den vorherigen Inhalt zu überschreiben.

!!! tip "Tipp"

    So, behind the scenes, it will actually work as if everything was the same single app.

!!! check
    You don't have to worry about performance when including routers.

    This will take microseconds and will only happen at startup.

    So it won't affect performance. ⚡

### Include an `APIRouter` with a custom `prefix`, `tags`, `responses`, and `dependencies`

```Python
async def do_something():
    try:
        yield something
    finally:
        some_cleanup()
```

...that way the `finally` block is run regardless of any exception that might happen.

### Features

* The same PR [#4575](https://github.com/tiangolo/fastapi/pull/4575) from above also fixes the `contextvars` context for the code before and after `yield`. This was the main objective of that PR.