Wir hatten diese Typannotation:

//// tab | Python 3.10+

```Python
q: str | None = None
```

////

//// tab | Python 3.9+

```Python
q: Union[str, None] = None
```

////

Was wir tun werden, ist, dies mit `Annotated` zu wrappen, sodass es zu:

//// tab | Python 3.10+

```Python
q: Annotated[str | None] = None
```

////

//// tab | Python 3.9+

```Python

Tínhamos esta anotação de tipo:

//// tab | Python 3.10+

```Python
q: str | None = None
```

////

//// tab | Python 3.9+

```Python
q: Union[str, None] = None
```

////

O que faremos é envolver isso com `Annotated`, para que fique assim:

//// tab | Python 3.10+

```Python
q: Annotated[str | None] = None
```

////

//// tab | Python 3.9+

```Python

class Item(BaseModel):
    name: Union[str, None] = None
    description: Union[str, None] = None
    price: Union[float, None] = None
    tax: float = 10.5
    tags: list[str] = []


items = {
    "foo": {"name": "Foo", "price": 50.2},
    "bar": {"name": "Bar", "description": "The bartenders", "price": 62, "tax": 20.2},
    "baz": {"name": "Baz", "description": None, "price": 50.2, "tax": 10.5, "tags": []},
}

                       var_name,
                       query_item,
                       enabled_by_default,
                       question=None,
                       yes_reply=None,
                       no_reply=None,
                       bazel_config_name=None):
  """Set boolean action_env variable.

  Ask user if query_item will be enabled. Default is used if no input is given.

            "price": 50.5,
            "description": None,
            "tax": None,
        },
        "user": {"username": "Dave", "full_name": None},
    }


def test_put_missing_body(client: TestClient):
    response = client.put("/items/5")
    assert response.status_code == 422
    assert response.json() == {
        "detail": [
            {
                "input": None,
                "loc": [

    github_repository: str
    github_token: SecretStr
    deploy_url: str | None = None
    commit_sha: str
    run_id: int
    state: Literal["pending", "success", "error"] = "pending"


class LinkData(BaseModel):
    previous_link: str
    preview_link: str
    en_link: str | None = None


def main() -> None:
    logging.basicConfig(level=logging.INFO)
    settings = Settings()

        dependencies: Optional[Sequence[Depends]] = None,
        summary: Optional[str] = None,
        description: Optional[str] = None,
        response_description: str = "Successful Response",
        responses: Optional[dict[Union[int, str], dict[str, Any]]] = None,
        deprecated: Optional[bool] = None,
        methods: Optional[list[str]] = None,
        operation_id: Optional[str] = None,

```Python
q: Union[str, None] = None
```

Ou bien, en Python 3.10 et supérieur :

```Python
q: str | None = None
```

Par exemple :

{* ../../docs_src/body_multiple_params/tutorial004_an_py310.py hl[27] *}

/// info

    return True


@noop_wrap
def wrapped_gen_dependency() -> Generator[bool, None, None]:
    yield True


@noop_wrap
async def async_wrapped_dependency() -> bool:
    return True


@noop_wrap
async def async_wrapped_gen_dependency() -> AsyncGenerator[bool, None]:
    yield True


@app.get("/wrapped-dependency/")

app = FastAPI()


class Image(BaseModel):
    url: str
    name: str


class Item(BaseModel):
    name: str
    description: str | None = None
    price: float
    tax: float | None = None
    tags: set[str] = set()
    image: Image | None = None


@app.put("/items/{item_id}")
async def update_item(item_id: int, item: Item):
    results = {"item_id": item_id, "item": item}