```

It will be used in the interactive docs:

<img src="/img/tutorial/path-operation-configuration/image02.png">

## Response description

You can specify the response description with the parameter `response_description`:

=== "Python 3.10+"

    ```Python hl_lines="19"
    {!> ../../../docs_src/path_operation_configuration/tutorial005_py310.py!}
    ```

If you select "Watching" instead of "Releases only" you will receive notifications when someone creates a new issue or question. You can also specify that you only want to be notified about new issues, or discussions, or PRs, etc.

Then you can try and help them solve those questions.

## Ask Questions

        * In responses, the `set` will be converted to a `list`.
        * The generated schema will specify that the `set` values are unique (using JSON Schema's `uniqueItems`).
* `bytes`:
    * Standard Python `bytes`.
    * In requests and responses will be treated as `str`.
    * The generated schema will specify that it's a `str` with `binary` "format".
* `Decimal`:
    * Standard Python `Decimal`.

Let's look at how we can make that work.

## pytest.mark.anyio

If we want to call asynchronous functions in our tests, our test functions have to be asynchronous. AnyIO provides a neat plugin for this, that allows us to specify that some test functions are to be called asynchronously.

## HTTPX

Even if your **FastAPI** application uses normal `def` functions instead of `async def`, it is still an `async` application underneath.

Because this dependency function doesn't have any scope requirements itself, we can use `Depends` with `oauth2_scheme`, we don't have to use `Security` when we don't need to specify security scopes.

We also declare a special parameter of type `SecurityScopes`, imported from `fastapi.security`.

This `SecurityScopes` class is similar to `Request` (`Request` was used to get the request object directly).

}
```

Of course, you will probably find much better ways to take advantage of this than formatting JSON. 😉

## Default response class

When creating a **FastAPI** class instance or an `APIRouter` you can specify which response class to use by default.

The parameter that defines this is `default_response_class`.

```Python hl_lines="16-18  21-22  25-30  34-35  38-39  42-48"
{!../../../docs_src/sql_databases_peewee/sql_app/schemas.py!}
```

!!! tip
    Here we are creating the models with an `id`.

    We didn't explicitly specify an `id` attribute in the Peewee models, but Peewee adds one automatically.

    We are also adding the magic `owner_id` attribute to `Item`.

### Create a `PeeweeGetterDict` for the Pydantic *models* / schemas

So, for everything to work correctly, it's better to specify explicitly the allowed origins.

## Use `CORSMiddleware`

You can configure it in your **FastAPI** application using the `CORSMiddleware`.

* Import `CORSMiddleware`.
* Create a list of allowed origins (as strings).
* Add it as a "middleware" to your **FastAPI** application.

You can also specify if your backend allows:

### OAuth 1

There was an OAuth 1, which is very different from OAuth2, and more complex, as it included direct specifications on how to encrypt the communication.

It is not very popular or used nowadays.

OAuth2 doesn't specify how to encrypt the communication, it expects you to have your application served with HTTPS.

!!! tip
    In the section about **deployment** you will see how to set up HTTPS for free, using Traefik and Let's Encrypt.

```Python hl_lines="19-24  28"
{!../../../docs_src/additional_responses/tutorial002.py!}
```

!!! note
    Notice that you have to return the image using a `FileResponse` directly.

!!! info
    Unless you specify a different media type explicitly in your `responses` parameter, FastAPI will assume the response has the same media type as the main response class (default `application/json`).