## Primeira dependência "dependable" { #first-dependency-dependable }

Você pode criar uma primeira dependência ("dependable") dessa forma:

{* ../../docs_src/dependencies/tutorial005_an_py310.py hl[8:9] *}

Esse código declara um parâmetro de consulta opcional, `q`, com o tipo `str`, e então retorna esse parâmetro.

### Import `Depends` { #import-depends }

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

### Declare the dependency, in the "dependant" { #declare-the-dependency-in-the-dependant }

The same way you use `Body`, `Query`, etc. with your *path operation function* parameters, use `Depends` with a new parameter:

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

### Импорт `Depends` { #import-depends }

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

### Объявите зависимость в «зависимом» { #declare-the-dependency-in-the-dependant }

Точно так же, как вы используете `Body`, `Query` и т. д. с параметрами вашей *функции обработки пути*, используйте `Depends` с новым параметром:

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

@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial001_py39"),
        pytest.param("tutorial001_py310", marks=needs_py310),
        pytest.param("tutorial001_an_py39"),
        pytest.param("tutorial001_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(f"docs_src.custom_request_and_route.{request.param}")

    @mod.app.get("/check-class")

{* ../../docs_src/security/tutorial004_an_py310.py hl[90:107] *}

## Die *Pfadoperation* `/token` aktualisieren { #update-the-token-path-operation }

Erstellen Sie ein <abbr title="Zeitdifferenz">`timedelta`</abbr> mit der Ablaufzeit des Tokens.

Erstellen Sie einen echten JWT-Zugriffstoken und geben Sie ihn zurück.

{* ../../docs_src/security/tutorial004_an_py310.py hl[118:133] *}

{* ../../docs_src/security/tutorial004_an_py310.py hl[90:107] *}

## Actualizar la *path operation* `/token` { #update-the-token-path-operation }

Crea un `timedelta` con el tiempo de expiración del token.

Crea un verdadero token de acceso JWT y devuélvelo.

{* ../../docs_src/security/tutorial004_an_py310.py hl[118:133] *}

## Import `Path` { #import-path }

First, import `Path` from `fastapi`, and import `Annotated`:

{* ../../docs_src/path_params_numeric_validations/tutorial001_an_py310.py hl[1,3] *}

/// info

FastAPI added support for `Annotated` (and started recommending it) in version 0.95.0.

If you have an older version, you would get errors when trying to use `Annotated`.

If the token is invalid, return an HTTP error right away.

{* ../../docs_src/security/tutorial004_an_py310.py hl[90:107] *}

## Update the `/token` *path operation* { #update-the-token-path-operation }

Create a `timedelta` with the expiration time of the token.

Create a real JWT access token and return it.

{* ../../docs_src/security/tutorial004_an_py310.py hl[118:133] *}

### `OAuth2PasswordRequestForm` { #oauth2passwordrequestform }

Primeiro, importe `OAuth2PasswordRequestForm` e use-o como uma dependência com `Depends` na *operação de rota* para `/token`:

{* ../../docs_src/security/tutorial003_an_py310.py hl[4,78] *}

`OAuth2PasswordRequestForm` é uma dependência de classe que declara um corpo de formulário com:

* O `username`.
* A `password`.

@pytest.fixture(
    name="client",
    params=[
        pytest.param("tutorial014_py39"),
        pytest.param("tutorial014_py310", marks=needs_py310),
        pytest.param("tutorial014_an_py39"),
        pytest.param("tutorial014_an_py310", marks=needs_py310),
    ],
)
def get_client(request: pytest.FixtureRequest):
    mod = importlib.import_module(
        f"docs_src.query_params_str_validations.{request.param}"
    )