```Python hl_lines="19-21"
    {!> ../../../docs_src/body_multiple_params/tutorial001.py!}
    ```

!!! note
    Notice that, in this case, the `item` that would be taken from the body is optional. As it has a `None` default value.

## Multiple body parameters

In the previous example, the *path operations* would expect a JSON body with the attributes of an `Item`, like:

```JSON
{

Würden Sie eine hierfür eine Rückgabetyp-Annotation verwenden, dann würden Tools und Editoren (korrekterweise) Fehler ausgeben, die Ihnen sagen, dass Ihre Funktion einen Typ zurückgibt (z. B. ein Dict), der sich unterscheidet von dem, was Sie deklariert haben (z. B. ein Pydantic-Modell).

You can learn how to use them and how they are integrated into **FastAPI** later in the **Advanced User Guide**.

## Recap

With what you have seen up to now, you can set up a secure **FastAPI** application using standards like OAuth2 and JWT.

In almost any framework handling the security becomes a rather complex subject quite quickly.

    ```

Beachten Sie, dass der Defaultwert immer noch `None` ist, sodass der Parameter immer noch optional ist.

    * This allows declaring a parameter like `user_id: str = None` that can be taken from a query parameter, but the same *path operation* can be included in a router with a path `/users/{user_id}`, in which case will be taken from the path and will be required.
    * PR [#464](https://github.com/tiangolo/fastapi/pull/464) by [@jonathanunderwood](https://github.com/jonathanunderwood).

{!../../../docs_src/templates/templates/item.html!}
```

### Template Context Values

In the HTML that contains:

{% raw %}

```jinja
Item ID: {{ id }}
```

{% endraw %}

...it will show the `id` taken from the "context" `dict` you passed:

```Python
{"id": id}
```

For example, with an ID of `42`, this would render:

```html
Item ID: 42
```

### Template `url_for` Arguments

```JSON
{
    "message": "Hello World",
    "root_path": "/api/v1"
}
```

!!! tip
    Notice that even though you are accessing it at `http://127.0.0.1:8000/app` it shows the `root_path` of `/api/v1`, taken from the option `--root-path`.

And now open the URL with the port for Traefik, including the path prefix: <a href="http://127.0.0.1:9999/api/v1/app" class="external-link" target="_blank">http://127.0.0.1:9999/api/v1/app</a>.

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-04-swagger-03.png)

* Then click on the "Execute" button, the user interface will communicate with your API, send the parameters, get the results and show them on the screen:

![Swagger UI interaction](https://fastapi.tiangolo.com/img/index/index-05-swagger-04.png)

### Alternative API docs upgrade

    ```

Python selbst macht nichts mit `Annotated`. Für Editoren und andere Tools ist der Typ immer noch `str`.

Aber Sie können `Annotated` nutzen, um **FastAPI** mit Metadaten zu versorgen, die ihm sagen, wie sich ihre Anwendung verhalten soll.

Wichtig ist, dass **der erste *Typ-Parameter***, den Sie `Annotated` übergeben, der **tatsächliche Typ** ist. Der Rest sind Metadaten für andere Tools.

These ORMs also have tools to make the connections or relations between tables or entities.

This way, you could also have an attribute `orion_cat.owner` and the owner would contain the data for this pet's owner, taken from the table *owners*.

So, `orion_cat.owner.name` could be the name (from the `name` column in the `owners` table) of this pet's owner.

It could have a value like `"Arquilian"`.