```Python hl_lines="9"
{!../../../docs_src/behind_a_proxy/tutorial004.py!}
```

and then it won't include it in the OpenAPI schema.

## Mounting a sub-application

If you need to mount a sub-application (as described in [Sub Applications - Mounts](sub-applications.md){.internal-link target=_blank}) while also using a proxy with `root_path`, you can do it normally, as you would expect.

![ReDoc](https://fastapi.tiangolo.com/img/index/index-06-redoc-02.png)

### Összefoglalás

Összegzésül, deklarálod **egyszer** a paraméterek, body, stb típusát funkciós paraméterekként.

Ezt standard modern Python típusokkal csinálod.

Nem kell új szintaxist, vagy specifikus könyvtár mert metódósait, stb. megtanulnod.

Csak standard **Python**.

Például egy `int`-nek:

```Python
item_id: int
```

## 0.4.0

* Add `openapi_prefix`, support for reverse proxy and mounting sub-applications. See the docs at [https://fastapi.tiangolo.com/advanced/sub-applications-proxy/](https://fastapi.tiangolo.com/advanced/sub-applications-proxy/): [#26](https://github.com/tiangolo/fastapi/pull/26) by [@kabirkhan](https://github.com/kabirkhan).

    - tutorial/encoder.md
    - tutorial/body-updates.md
    - Dependencies:
      - tutorial/dependencies/index.md
      - tutorial/dependencies/classes-as-dependencies.md
      - tutorial/dependencies/sub-dependencies.md
      - tutorial/dependencies/dependencies-in-path-operation-decorators.md
      - tutorial/dependencies/global-dependencies.md
      - tutorial/dependencies/dependencies-with-yield.md
    - Security:

**FastAPI** is fully compatible with (and based on) <a href="https://www.starlette.io/" class="external-link" target="_blank"><strong>Starlette</strong></a>. So, any additional Starlette code you have, will also work.

`FastAPI` is actually a sub-class of `Starlette`. So, if you already know or use Starlette, most of the functionality will work the same way.

With **FastAPI** you get all of **Starlette**'s features (as FastAPI is just Starlette on steroids):

# Including WSGI - Flask, Django, others

You can mount WSGI applications as you saw with [Sub Applications - Mounts](sub-applications.md){.internal-link target=_blank}, [Behind a Proxy](behind-a-proxy.md){.internal-link target=_blank}.

For that, you can use the `WSGIMiddleware` and use it to wrap your WSGI application, for example, Flask, Django, etc.

## Using `WSGIMiddleware`

You need to import `WSGIMiddleware`.

### Create the `Settings` object

Import `BaseSettings` from Pydantic and create a sub-class, very much like with a Pydantic model.

The same way as with Pydantic models, you declare class attributes with type annotations, and possibly default values.