Спочатку просто запустімо код і подивімося, як він працює, а потім повернемося, щоб розібратися, що відбувається.

## Створіть `main.py` { #create-main-py }

Скопіюйте приклад у файл `main.py`:

{* ../../docs_src/security/tutorial001_an_py310.py *}

## Запустіть { #run-it }

/// info | Інформація

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[3] *}

### "Dependant" İçinde Dependency'yi Tanımlayın { #declare-the-dependency-in-the-dependant }

*Path operation function* parametrelerinizde `Body`, `Query` vb. kullandığınız gibi, yeni bir parametreyle `Depends` kullanın:

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[13,18] *}

Pour y parvenir, importez `JSONResponse` et renvoyez-y directement votre contenu, en définissant le `status_code` que vous souhaitez :

{* ../../docs_src/additional_status_codes/tutorial001_an_py310.py hl[4,25] *}

/// warning | Alertes

Lorsque vous renvoyez une `Response` directement, comme dans l'exemple ci-dessus, elle sera renvoyée directement.

Elle ne sera pas sérialisée avec un modèle, etc.

这种情况下，会一直持有数据库会话直到响应发送完毕；但如果并不再使用它，就没有必要一直占用。

代码可能如下：

{* ../../docs_src/dependencies/tutorial013_an_py310.py *}

退出代码（自动关闭 `Session`）位于：

{* ../../docs_src/dependencies/tutorial013_an_py310.py ln[19:21] *}

...会在响应把慢速数据发送完之后才运行：

{* ../../docs_src/dependencies/tutorial013_an_py310.py ln[30:38] hl[31:33] *}

但由于 `generate_stream()` 并不使用数据库会话，因此在发送响应期间保持会话打开并非必要。

Así es como se vería:

{* ../../docs_src/dependencies/tutorial013_an_py310.py *}

El código de salida, el cierre automático de la `Session` en:

{* ../../docs_src/dependencies/tutorial013_an_py310.py ln[19:21] *}

...se ejecutaría después de que la response termine de enviar los datos lentos:

{* ../../docs_src/dependencies/tutorial013_an_py310.py ln[30:38] hl[31:33] *}

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[3] *}

### Declarando a dependência, no "dependente" { #declare-the-dependency-in-the-dependant }

Da mesma forma que você utiliza `Body`, `Query`, etc. Como parâmetros de sua *função de operação de rota*, utilize `Depends` com um novo parâmetro:

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[13,18] *}

from inline_snapshot import snapshot

from ...utils import needs_py310


@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial001_py310", marks=needs_py310),
        pytest.param("tutorial001_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.body_multiple_params.{request.param}")

    client = TestClient(mod.app)

Örneğin, varsayılan `401 Unauthorized` hatası yerine `403 Forbidden` hatası döndüren bir `HTTPBearer` alt sınıfı oluşturabilirsiniz:

{* ../../docs_src/authentication_error_status_code/tutorial001_an_py310.py hl[9:13] *}

/// tip | İpucu

Fonksiyonun exception instance'ını döndürdüğüne dikkat edin; exception'ı raise etmiyor. Raise işlemi internal kodun geri kalan kısmında yapılıyor.

For example, you can create a subclass of `HTTPBearer` that returns a `403 Forbidden` error instead of the default `401 Unauthorized` error:

{* ../../docs_src/authentication_error_status_code/tutorial001_an_py310.py hl[9:13] *}

/// tip

Notice that the function returns the exception instance, it doesn't raise it. The raising is done in the rest of the internal code.

Por exemplo, você pode criar uma subclasse de `HTTPBearer` que retorne um erro `403 Forbidden` em vez do erro padrão `401 Unauthorized`:

{* ../../docs_src/authentication_error_status_code/tutorial001_an_py310.py hl[9:13] *}

/// tip | Dica

Perceba que a função retorna a instância da exceção, ela não a lança. O lançamento é feito no restante do código interno.