```Python
    return {"item_name": item.name, "item_id": item_id}
```

...da:

```Python
        ... "item_name": item.name ...
```

...a:

```Python
        ... "item_price": item.price ...
```

...e osserva come il tuo editor di testo autocompleterà gli attributi e sarà in grado di riconoscere i loro tipi:

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

    response = client.post("/items/", json={"name": "Foo", "price": 50.5})
    assert response.status_code == 200
    assert response.json() == {
        "name": "Foo",
        "price": 50.5,
        "description": None,
        "tax": None,
    }


@needs_py310
def test_post_with_str_float(client: TestClient):
    response = client.post("/items/", json={"name": "Foo", "price": "50.5"})
    assert response.status_code == 200

    response = client.post("/items/", json={"name": "Foo", "price": 50.5})
    assert response.status_code == 200
    assert response.json() == {
        "name": "Foo",
        "price": 50.5,
        "description": None,
        "tax": None,
    }


def test_post_with_str_float(client: TestClient):
    response = client.post("/items/", json={"name": "Foo", "price": "50.5"})
    assert response.status_code == 200

        "description": None,
        "price": 50.2,
        "tax": 10.5,
        "tags": [],
    }


@needs_py39
def test_put(client: TestClient):
    response = client.put(
        "/items/bar", json={"name": "Barz", "price": 3, "description": None}
    )
    assert response.json() == {
        "name": "Barz",
        "description": None,
        "price": 3,
        "tax": 10.5,
        "tags": [],

... rend le paramètre optionnel, et est donc équivalent à :

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

Mais déclare explicitement `q` comme étant un paramètre de requête.

!!! info
    Gardez à l'esprit que la partie la plus importante pour rendre un paramètre optionnel est :

    ```Python
    = None
    ```

    ou :

    ```Python
    = Query(None)
    ```

```Python
    return {"item_name": item.name, "item_id": item_id}
```

...z:

```Python
        ... "item_name": item.name ...
```

...na:

```Python
        ... "item_price": item.price ...
```

...i zobacz jak edytor kodu automatycznie uzupełni atrybuty i będzie znał ich typy:

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

```Python
    return {"item_name": item.name, "item_id": item_id}
```

...из:

```Python
        ... "item_name": item.name ...
```

...в:

```Python
        ... "item_price": item.price ...
```

... и посмотрите, как ваш редактор будет автоматически заполнять атрибуты и узнавать их типы:

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

```Python
    return {"item_name": item.name, "item_id": item_id}
```

......从：

```Python
        ... "item_name": item.name ...
```

......改为：

```Python
        ... "item_price": item.price ...
```

......注意观察编辑器是如何自动补全属性并且还知道它们的类型：

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

<a href="https://fastapi.tiangolo.com/zh/tutorial/">教程 - 用户指南</a> 中有包含更多特性的更完整示例。

    ```

Das würde bedeuten, dass **FastAPI** einen Body erwartet wie:

```JSON
{
    "name": "Foo",
    "description": "The pretender",
    "price": 42.0,
    "tax": 3.2,
    "tags": ["rock", "metal", "bar"],
    "image": {
        "url": "http://example.com/baz.jpg",
        "name": "The Foo live"
    }
}
```

You will also get autocompletion for the payload to send:

<img src="/img/tutorial/generate-clients/image03.png">

!!! tip
    Notice the autocompletion for `name` and `price`, that was defined in the FastAPI application, in the `Item` model.

You will have inline errors for the data that you send:

<img src="/img/tutorial/generate-clients/image04.png">