{
    "name": "Barz",
    "price": 3,
    "description": None,
}
```

因为上述数据未包含已存储的属性 `"tax": 20.2`，新的输入模型会把 `"tax": 10.5` 作为默认值。

因此，本次操作把 `tax` 的值「更新」为 `10.5`。

## 用 `PATCH` 进行部分更新

<a href="https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Methods/PATCH" class="external-link" target="_blank">HTTP `PATCH`</a> 操作用于更新 *部分* 数据。

即，只发送要更新的数据，其余数据保持不变。

!!! note "笔记"

    `PATCH` 没有 `PUT` 知名，也怎么不常用。

```Python hl_lines="19-24 28"
{!../../../docs_src/additional_responses/tutorial002.py!}
```

!!! note "Remarque"
    Notez que vous devez retourner l'image en utilisant directement un `FileResponse`.

!!! info

<span style="color: green;">INFO</span>:     Waiting for application startup.
<span style="color: green;">INFO</span>:     Application startup complete.
```

</div>

!!! note "Технические детали"
    Команда `uvicorn main:app` обращается к:

    * `main`: файл `main.py` (модуль Python).
    * `app`: объект, созданный внутри файла `main.py` в строке `app = FastAPI()`.

<div class="termy">

```console
$ pip install "fastapi[all]"

---> 100%
```

</div>

...isso também inclui o `uvicorn`, que você pode usar como o servidor que rodará seu código.

!!! note "Nota"
    Você também pode instalar parte por parte.

    Isso é provavelmente o que você faria quando você quisesse lançar sua aplicação em produção:

    ```
    pip install fastapi
    ```

!!! note
    Notice that as we communicate with the database using `await`, the *path operation function* is declared with `async`.

### About `{**note.dict(), "id": last_record_id}`

`note` is a Pydantic `Note` object.

`note.dict()` returns a `dict` with its data, something like:

```Python
{
    "text": "Some note",
    "completed": False,
}
```

{!../../../docs_src/app_testing/tutorial001.py!}
```

!!! tip
    Notice that the testing functions are normal `def`, not `async def`.

    And the calls to the client are also normal calls, not using `await`.

    This allows you to use `pytest` directly without complications.

!!! note "Technical Details"
    You could also use `from starlette.testclient import TestClient`.

<span style="color: green;">INFO</span>:     Waiting for application startup.
<span style="color: green;">INFO</span>:     Application startup complete.
```

</div>

!!! note
    📋 `uvicorn main:app` 🔗:

    * `main`: 📁 `main.py` (🐍 "🕹").
    * `app`: 🎚 ✍ 🔘 `main.py` ⏮️ ⏸ `app = FastAPI()`.
    * `--reload`: ⚒ 💽 ⏏ ⏮️ 📟 🔀. 🕴 ⚙️ 🛠️.

🔢, 📤 ⏸ ⏮️ 🕳 💖:

```hl_lines="4"

=== "Python 3.8+ non-Annotated"

    !!! tip
        Prefer to use the `Annotated` version if possible.

    ```Python hl_lines="9"
    {!> ../../../docs_src/cookie_params/tutorial001.py!}
    ```

!!! note "Detalles Técnicos"
    `Cookie` es una clase "hermana" de `Path` y `Query`. También hereda de la misma clase común `Param`.

<span style="color: green;">INFO</span>:     Waiting for application startup.
<span style="color: green;">INFO</span>:     Application startup complete.
```

</div>

!!! note "備考"
    `uvicorn main:app`は以下を示します:

    * `main`: `main.py`ファイル (Python "module")。
    * `app`:  `main.py`内部で作られるobject（`app = FastAPI()`のように記述される）。
    * `--reload`: コードの変更時にサーバーを再起動させる。開発用。

出力には次のような行があります:

!!! note "Technical Details"
    ASGI is a new "standard" being developed by Django core team members. It is still not a "Python standard" (a PEP), although they are in the process of doing that.