In previous versions of Python, you could have used threads or <a href="https://www.gevent.org/" class="external-link" target="_blank">Gevent</a>. But the code is way more complex to understand, debug, and think about.

In previous versions of NodeJS / Browser JavaScript, you would have used "callbacks". Which leads to <a href="http://callbackhell.com/" class="external-link" target="_blank">callback hell</a>.

* Editör desteğiyle birlikte:
    * Otomatik tamamlama.
    * Tip kontrolü.
* Veri Doğrulama:
    * Veri geçerli değilse, otomatik olarak açıklayıcı hatalar gösterir.
    * Çok <abbr title="Derin / İç içe: Nested">derin</abbr> JSON nesnelerinde bile doğrulama yapar.
* Gelen verinin <abbr title="Dönüşüm: serialization, parsing, marshalling olarak da biliniyor">dönüşümünü</abbr> aşağıdaki veri tiplerini kullanarak gerçekleştirir:
    * JSON.

!!! tip
    This will just make Peewee behave correctly when used with FastAPI. Not randomly opening or closing connections that are being used, creating errors, etc.

    assert response.json() == {"foo": "baz"}


def test_nested_router():
    app = FastAPI()

    router = APIRouter(prefix="/nested")

    @router.get("/test")
    async def test(var: Annotated[str, Query()] = "bar"):
        return {"foo": var}

    app.include_router(router)

    client = TestClient(app)

    response = client.get("/nested/test")
    assert response.status_code == 200

![editor support](https://fastapi.tiangolo.com/img/pycharm-completion.png)


Daha önceden düşünüp en imkansız diyebileceğin durumlarda bile otomatik tamamlama alacaksın, örnek olarak `price` JSON body içerisinde (nested bir JSON body de olabilirdi.) direkt olarak istekten geliyor, bu durumda bile oto-tammalama sağlıyor.

    * Check that it has an optional attribute `is_offer`, that should be a `bool`, if present.
    * All this would also work for deeply nested JSON objects.
* Convert from and to JSON automatically.
* Document everything with OpenAPI, that can be used by:
    * Interactive documentation systems.
    * Automatic client code generation systems, for many languages.

It is also built to work as a future reference.

So you can come back and see exactly what you need.

## Run the code

All the code blocks can be copied and used directly (they are actually tested Python files).

To run any of the examples, copy the code to a file `main.py`, and start `fastapi dev` with:

<div class="termy">

```console

import pytest
from dirty_equals import IsDict
from fastapi.testclient import TestClient

from ...utils import needs_py39


@pytest.fixture(name="client")
def get_client():
    from docs_src.body_nested_models.tutorial009_py39 import app

    client = TestClient(app)
    return client


@needs_py39
def test_post_body(client: TestClient):
    data = {"2": 2.2, "3": 3.3}
    response = client.post("/index-weights/", json=data)

        model_name_map: Dict[Union[Type[BaseModel], Type[Enum]], str],
    ) -> Dict[str, Any]:
        definitions: Dict[str, Dict[str, Any]] = {}
        for model in flat_models:
            m_schema, m_definitions, m_nested_models = model_process_schema(
                model, model_name_map=model_name_map, ref_prefix=REF_PREFIX
            )
            definitions.update(m_definitions)
            model_name = model_name_map[model]

Insbesondere können Sie <a href="https://anyio.readthedocs.io/en/stable/" class="external-link" target="_blank">AnyIO</a> direkt verwenden für Ihre fortgeschritten nebenläufigen und parallelen Anwendungsfälle, die fortgeschrittenere Muster in Ihrem eigenen Code erfordern.