def __init__(
        self,
        *,
        grant_type: Annotated[
            Union[str, None],
            Form(pattern="password"),
            Doc(
                """
                The OAuth2 spec says it is required and MUST be the fixed string
                "password". Nevertheless, this dependency class is permissive and
                allows not passing it. If you want to enforce it, use instead the

OAuth2 specifies that when using the "password flow" (that we are using) the client/user must send a `username` and `password` fields as form data.

And the spec says that the fields have to be named like that. So `user-name` or `email` wouldn't work.

But don't worry, you can show it as you wish to your final users in the frontend.

And your database models can use any other names you want.

    ```Python hl_lines="115-130"
    {!> ../../../docs_src/security/tutorial004.py!}
    ```

### Technical details about the JWT "subject" `sub`

The JWT specification says that there's a key `sub`, with the subject of the token.

It's optional to use it, but that's where you would put the user's identification, so we are using it here.

So you wait for your crush to finish the story (finish the current work ⏯ / task being processed 🤓), smile gently and say that you are going for the burgers ⏸.

Now you can translate it all and see how it looks as you save the file.

#### New Language

Let's say that you want to add translations for a language that is not yet translated, not even some pages.

Let's say you want to add translations for Creole, and it's not yet there in the docs.

Checking the link from above, the code for "Creole" is `ht`.

                This is useful when you want to have optional authentication.

                It is also useful when you want to have authentication that can be
                provided in one of multiple optional ways (for example, in HTTP Basic
                authentication or in an HTTP Bearer token).
                """
            ),
        ] = True,
    ):

{% endif %}

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## Opinie

"_[...] I'm using **FastAPI** a ton these days. [...] I'm actually planning to use it for all of my team's **ML services at Microsoft**. Some of them are getting integrated into the core **Windows** product and some **Office** products._"

{% endif %}

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## Recensioni

"_[...] I'm using **FastAPI** a ton these days. [...] I'm actually planning to use it for all of my team's **ML services at Microsoft**. Some of them are getting integrated into the core **Windows** product and some **Office** products._"

!!! check "Inspired **FastAPI** to"
    Find ways to get great performance.

    Along with Hug (as Hug is based on Falcon) inspired **FastAPI** to declare a `response` parameter in functions.

Si vous vous sentez perdu avec le concept d'**expression régulière**, pas d'inquiétudes. Il s'agit d'une notion difficile pour beaucoup, et l'on peut déjà réussir à faire beaucoup sans jamais avoir à les manipuler.

Mais si vous décidez d'apprendre à les utiliser, sachez qu'ensuite vous pouvez les utiliser directement dans **FastAPI**.

## Valeurs par défaut