* If you are comparing Uvicorn, compare it against Daphne, Hypercorn, uWSGI, etc. Application servers.
* **Starlette**:

{% if sponsors %}

{% if sponsors.gold %}

### Qızıl Sponsorlar

{% for sponsor in sponsors.gold -%}
<a href="{{ sponsor.url }}" target="_blank" title="{{ sponsor.title }}"><img src="{{ sponsor.img }}" style="border-radius:15px"></a>
{% endfor %}
{% endif %}

{% if sponsors.silver %}

### Gümüş Sponsorlar

{% if sponsors %}

{% if sponsors.gold %}

### Altın Sponsorlar

{% for sponsor in sponsors.gold -%}
<a href="{{ sponsor.url }}" target="_blank" title="{{ sponsor.title }}"><img src="{{ sponsor.img }}" style="border-radius:15px"></a>
{% endfor %}
{% endif %}

{% if sponsors.silver %}

### Gümüş Sponsorlar

!!! tip
    If you have strict type checks in your editor, mypy, etc, you can declare the function return type as `Any`.

    That way you tell the editor that you are intentionally returning anything. But FastAPI will still do the data documentation, validation, filtering, etc. with the `response_model`.

### `response_model` Priority

You can check it at <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs</a>:

<img src="/img/tutorial/behind-a-proxy/image01.png">

    ```

=== "Python 3.10+ non-Annotated"

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="1"
    {!> ../../../docs_src/cookie_params/tutorial001_py310.py!}
    ```

=== "Python 3.8+ non-Annotated"

    !!! tip
        Prefer to use the `Annotated` version if possible.

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

This also means that if something changed it will be **reflected** on the client code automatically. And if you **build** the client it will error out if you have any **mismatch** in the data used.

    ```

=== "Python 3.10+ non-Annotated"

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python
    {!> ../../../docs_src/app_testing/app_b_py310/main.py!}
    ```

=== "Python 3.8+ non-Annotated"

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python
    {!> ../../../docs_src/app_testing/app_b/main.py!}
    ```

```Python hl_lines="6-7"
{!../../../docs_src/path_params/tutorial001.py!}
```

The value of the path parameter `item_id` will be passed to your function as the argument `item_id`.

So, if you run this example and go to <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a>, you will see a response of:

```JSON
{"item_id":"foo"}
```

!!! info
    Keep in mind that dataclasses can't do everything Pydantic models can do.

    So, you might still need to use Pydantic models.

    But if you have a bunch of dataclasses laying around, this is a nice trick to use them to power a web API using FastAPI. 🤓

## Dataclasses in `response_model`

You can also use `dataclasses` in the `response_model` parameter: