## Instalar `PyJWT` { #install-pyjwt }

Nós precisamos instalar o `PyJWT` para criar e verificar os tokens JWT em Python.

Certifique-se de criar um [ambiente virtual](../../virtual-environments.md){.internal-link target=_blank}, ativá-lo e então instalar o `pyjwt`:

<div class="termy">

```console
$ pip install pyjwt

---> 100%

{* ../../docs_src/custom_request_and_route/tutorial001_an_py310.py hl[19:27] *}

/// note | Technische Details

Ein `Request` hat ein `request.scope`-Attribut, welches einfach ein Python-<abbr title="Dictionary – Zuordnungstabelle: In anderen Sprachen auch Hash, Map, Objekt, Assoziatives Array genannt">`dict`</abbr> ist, welches die mit dem Request verbundenen Metadaten enthält.

### Warnung bezüglich des Ersetzens { #warning-about-replacing }

Das bedeutet, dass, wenn Sie den Artikel `bar` aktualisieren wollen, mittels `PUT` und folgendem Body:

```Python
{
    "name": "Barz",
    "price": 3,
    "description": None,
}
```

weil das bereits gespeicherte Attribut `"tax": 20.2` nicht enthalten ist, das Eingabemodell den Defaultwert `"tax": 10.5` erhalten würde.

    * Unless it's a feature we want to discourage, like support for a corner case that we don't want users to use.
* The docs should include a source example file, not write Python directly in Markdown.
* If the source example(s) file can have different syntax for different Python versions, there should be different versions of the file, and they should be shown in tabs in the docs.
* There should be tests testing the source example.

* PostgreSQL
* MySQL
* SQLite
* Oracle
* Microsoft SQL Server, etc.

Neste exemplo, usaremos **SQLite**, porque ele usa um único arquivo e o Python tem suporte integrado. Assim, você pode copiar este exemplo e executá-lo como está.

Mais tarde, para sua aplicação em produção, você pode querer usar um servidor de banco de dados como o **PostgreSQL**.

/// tip | Dica

Aber FastAPI unterstützt auf die gleiche Weise auch die Verwendung von <a href="https://docs.python.org/3/library/dataclasses.html" class="external-link" target="_blank">`dataclasses`</a>:

{* ../../docs_src/dataclasses_/tutorial001_py310.py hl[1,6:11,18:19] *}

# Using Dataclasses { #using-dataclasses }

FastAPI is built on top of **Pydantic**, and I have been showing you how to use Pydantic models to declare requests and responses.

But FastAPI also supports using <a href="https://docs.python.org/3/library/dataclasses.html" class="external-link" target="_blank">`dataclasses`</a> the same way:

{* ../../docs_src/dataclasses_/tutorial001_py310.py hl[1,6:11,18:19] *}

```

...and another console code example...

```console
// Create a directory "Code"
$ mkdir code
// Switch into that directory
$ cd code
```

...and a Python code example...

```Python
wont_work()  # This won't work 😱
works(foo="bar")  # This works 🎉
```

...and that's it.

////

//// tab | Info

                warnings.simplefilter(
                    "ignore", category=UnsupportedFieldAttributeWarning
                )
            # TODO: remove after dropping support for Python 3.8 and
            # setting the min Pydantic to v2.12.3 that adds asdict()
            field_dict = asdict(self.field_info)
            annotated_args = (
                field_dict["annotation"],

    Read more about it in the
    [FastAPI docs for Bigger Applications - Multiple Files](https://fastapi.tiangolo.com/tutorial/bigger-applications/).

    ## Example

    ```python
    from fastapi import APIRouter, FastAPI

    app = FastAPI()
    router = APIRouter()


    @router.get("/users/", tags=["users"])
    async def read_users():