return HTTPAuthorizationCredentials(scheme=scheme, credentials=credentials)


class HTTPBasic(HTTPBase):
    """
    HTTP Basic authentication.

    ## Usage

    Create an instance object and use that object as the dependency in `Depends()`.

    The dependency result will be an `HTTPBasicCredentials` object containing the
    `username` and the `password`.

    Read more about it in the

# Static Files

You can serve static files automatically from a directory using `StaticFiles`.

## Use `StaticFiles`

* Import `StaticFiles`.
* "Mount" a `StaticFiles()` instance in a specific path.

```Python hl_lines="2  6"
{!../../../docs_src/static_files/tutorial001.py!}
```

!!! note "Technical Details"
    You could also use `from starlette.staticfiles import StaticFiles`.

            scope=scope,
            client_id=client_id,
            client_secret=client_secret,
        )


class OAuth2(SecurityBase):
    """
    This is the base class for OAuth2 authentication, an instance of it would be used
    as a dependency. All other OAuth2 classes inherit from it and customize it for
    each OAuth2 flow.

    You normally would not create a new class inheriting from it but use one of the

### Step 2: create a `FastAPI` "instance"

```Python hl_lines="3"
{!../../../docs_src/first_steps/tutorial001.py!}
```

Here the `app` variable will be an "instance" of the class `FastAPI`.

This will be the main point of interaction to create all your API.

### Step 3: create a *path operation*

    Actually, `Query`, `Path` and others you'll see next create objects of subclasses of a common `Param` class, which is itself a subclass of Pydantic's `FieldInfo` class.

    And Pydantic's `Field` returns an instance of `FieldInfo` as well.

    `Body` also returns objects of a subclass of `FieldInfo` directly. And there are others you will see later that are subclasses of the `Body` class.

    The `scope` `dict` and `receive` function are both part of the ASGI specification.

    And those two things, `scope` and `receive`, are what is needed to create a new `Request` instance.

    To learn more about the `Request` check <a href="https://www.starlette.io/requests/" class="external-link" target="_blank">Starlette's docs about Requests</a>.

Do you want to have an `id` and `email` and not have any `username` in your model? Sure. You can use these same tools.

Do you want to just have a `str`? Or just a `dict`? Or a database class model instance directly? It all works the same way.

You actually don't have users that log in to your application but robots, bots, or other systems, that have just an access token? Again, it all works the same.

    In that case, **FastAPI** also provides you with the tools to build it.

When we create an instance of the `OAuth2PasswordBearer` class we pass in the `tokenUrl` parameter. This parameter contains the URL that the client (the frontend running in the user's browser) will use to send the `username` and `password` in order to get a token.

But we want to be able to parameterize that fixed content.

## A "callable" instance

In Python there's a way to make an instance of a class a "callable".

Not the class itself (which is already a callable), but an instance of that class.

To do that, we declare a method `__call__`:

=== "Python 3.9+"

    ```Python hl_lines="12"

We annotate the function return type as `BaseUser`, but we are actually returning a `UserIn` instance.

The editor, mypy, and other tools won't complain about this because, in typing terms, `UserIn` is a subclass of `BaseUser`, which means it's a *valid* type when what is expected is anything that is a `BaseUser`.