É apenas uma função padrão que pode receber parâmetros.

Pode ser uma função `async def` ou um `def` normal, o **FastAPI** saberá como lidar com isso corretamente.

Neste caso, a função da tarefa escreverá em um arquivo (simulando o envio de um e-mail).

E como a operação de escrita não usa `async` e `await`, definimos a função com um `def` normal:

{* ../../docs_src/background_tasks/tutorial001_py39.py hl[6:9] *}

    path: str = route.path_format
    return generate_operation_id_for_path(name=route.name, path=path, method=method)


def generate_operation_summary(*, route: routing.APIRoute, method: str) -> str:
    if route.summary:
        return route.summary
    return route.name.replace("_", " ").title()


def get_openapi_operation_metadata(
    *, route: routing.APIRoute, method: str, operation_ids: set[str]
) -> dict[str, Any]:

from docs_src.additional_responses.tutorial003_py39 import app

client = TestClient(app)


def test_path_operation():
    response = client.get("/items/foo")
    assert response.status_code == 200, response.text
    assert response.json() == {"id": "foo", "value": "there goes my hero"}


def test_path_operation_not_found():
    response = client.get("/items/bar")
    assert response.status_code == 404, response.text

        pytest.param("tutorial001_py39"),
        pytest.param("tutorial001_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.response_directly.{request.param}")

    client = TestClient(mod.app)
    return client


def test_path_operation(client: TestClient):
    response = client.put(
        "/items/1",
        json={

from docs_src.app_testing.tutorial002_py39 import test_read_main, test_websocket


def test_main():
    test_read_main()


def test_ws():

Elle peut être une fonction asynchrone (`async def`) ou une fonction normale (`def`), **FastAPI** saura la gérer correctement.

Dans cet exemple, la fonction de tâche écrira dans un fichier (afin de simuler un envoi d'email).

L'opération d'écriture n'utilisant ni `async` ni `await`, on définit la fonction avec un `def` normal.

{* ../../docs_src/background_tasks/tutorial001.py hl[6:9] *}

        ),
        (
            "/items/baz?short=true",
            {"item_id": "baz"},
        ),
    ],
)
def test_read_user_item(client: TestClient, path, expected_json):
    response = client.get(path)
    assert response.status_code == 200
    assert response.json() == expected_json


def test_openapi_schema(client: TestClient):
    response = client.get("/openapi.json")
    assert response.status_code == 200

import base64, hashlib, sys
from mercurial import registrar, ui, hg, node
from mercurial.i18n import _
cmdtable = {}
command = registrar.command(cmdtable)
@command(b'goreposum', [], _('url'), norepo=True)
def goreposum(ui, url):
  """
  goreposum computes a checksum of all the named state in the remote repo.
  It hashes together all the branch names and hashes
  and then all the bookmark names and hashes.

You can define event handlers (functions) that need to be executed before the application starts up, or when the application is shutting down.

These functions can be declared with `async def` or normal `def`.

### `startup` event { #startup-event }

To add a function that should be run before the application starts, declare it with the event `"startup"`:

{* ../../docs_src/events/tutorial001_py39.py hl[8] *}

Você pode definir manipuladores de eventos (funções) que precisam ser executados antes de a aplicação iniciar ou quando a aplicação estiver encerrando.

Essas funções podem ser declaradas com `async def` ou `def` normal.

### Evento `startup` { #startup-event }

Para adicionar uma função que deve rodar antes de a aplicação iniciar, declare-a com o evento `"startup"`:

{* ../../docs_src/events/tutorial001_py39.py hl[8] *}