**FastAPI** gives you the following:

### Based on open standards { #based-on-open-standards }

* [**OpenAPI**](https://github.com/OAI/OpenAPI-Specification) for API creation, including declarations of <dfn title="also known as: endpoints, routes">path</dfn> <dfn title="also known as HTTP methods, as POST, GET, PUT, DELETE">operations</dfn>, parameters, request bodies, security, etc.

		return matches[1]
	}
	return "unknown"
}

func methodNotAllowedHandler(api string) func(w http.ResponseWriter, r *http.Request) {
	return errorResponseHandler
}

// If none of the http routes match respond with appropriate errors
func errorResponseHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method == http.MethodOptions {
		return
	}

* There's a subdirectory `app/routers/` with another file `__init__.py`, so it's a "Python subpackage": `app.routers`.
* The file `app/routers/items.py` is inside a package, `app/routers/`, so, it's a submodule: `app.routers.items`.
* The same with `app/routers/users.py`, it's another submodule: `app.routers.users`.

Examples:

Source (English):

```
<dfn title="also known as: endpoints, routes">path</dfn>
<dfn title="a program that checks for code errors">linter</dfn>
```

Result (German):

```
<dfn title="auch bekannt als: Endpunkte, Routen">Pfad</dfn>
<dfn title="Programm das auf Fehler im Code prüft">Linter</dfn>

{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[33] *}

/// tip | Tipp

Beachten Sie, dass Sie nicht den Router selbst (`invoices_callback_router`) an `callback=` übergeben, sondern das Attribut `.routes`, wie in `invoices_callback_router.routes`.

///

### Es in der Dokumentation testen { #check-the-docs }

                terms_of_service=self.terms_of_service,
                contact=self.contact,
                license_info=self.license_info,
                routes=self.routes,
                webhooks=self.webhooks.routes,
                tags=self.openapi_tags,
                servers=self.servers,
                separate_input_output_schemas=self.separate_input_output_schemas,

///

### Callback router'ını ekleyin { #add-the-callback-router }

Bu noktada, yukarıda oluşturduğunuz callback router'ında gerekli callback *path operation*'ları (external geliştiricinin *external API*'de implemente etmesi gerekenler) hazır.

Şimdi sizin API'nizin *path operation decorator*'ında `callbacks` parametresini kullanarak, callback router'ının `.routes` attribute'unu (bu aslında route/*path operation*'lardan oluşan bir `list`) geçin:

{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[33] *}

/// tip | Consejo

Observa que no estás pasando el router en sí (`invoices_callback_router`) a `callback=`, sino el atributo `.routes`, como en `invoices_callback_router.routes`.

///

### Revisa la documentación { #check-the-docs }

Ahora puedes iniciar tu aplicación e ir a [http://127.0.0.1:8000/docs](http://127.0.0.1:8000/docs).

        title="Custom title",
        version="2.5.0",
        summary="This is a very custom OpenAPI schema",
        description="Here's a longer description of the custom **OpenAPI** schema",
        routes=app.routes,
    )
    openapi_schema["info"]["x-logo"] = {
        "url": "https://fastapi.tiangolo.com/img/logo-margin/logo-teal.png"
    }
    app.openapi_schema = openapi_schema
    return app.openapi_schema

{* ../../docs_src/openapi_callbacks/tutorial001_py310.py hl[33] *}

/// tip | Совет

Обратите внимание, что вы передаёте не сам маршрутизатор (`invoices_callback_router`) в `callback=`, а его атрибут `.routes`, то есть `invoices_callback_router.routes`.

///

### Проверьте документацию { #check-the-docs }

Теперь вы можете запустить приложение и перейти по адресу [http://127.0.0.1:8000/docs](http://127.0.0.1:8000/docs).