}

  public void testFinalizeClassHasNoNestedClasses() throws Exception {
    // Ensure that the Finalizer class has no nested classes.
    // See https://github.com/google/guava/issues/1505
    assertEquals(Collections.emptyList(), Arrays.asList(Finalizer.class.getDeclaredClasses()));
  }

응답 모델은 아래와 같이 기본값을 가질 수 있습니다:

```Python hl_lines="11  13-14"
{!../../docs_src/response_model/tutorial004.py!}
```

* `description: Optional[str] = None`은 기본값으로 `None`을 갖습니다.
* `tax: float = 10.5`는 기본값으로 `10.5`를 갖습니다.
* `tags: List[str] = []` 빈 리스트의 기본값으로: `[]`.

그러나 실제로 저장되지 않았을 경우 결과에서 값을 생략하고 싶을 수 있습니다.

예를 들어, NoSQL 데이터베이스에 많은 선택적 속성이 있는 모델이 있지만, 기본값으로 가득 찬 매우 긴 JSON 응답을 보내고 싶지 않습니다.

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    *,
    item_id: Annotated[int, Path(title="The ID of the item to get", ge=0, le=1000)],
    q: str,
    size: Annotated[float, Query(gt=0, lt=10.5)],
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})
    if size:
        results.update({"size": size})

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    *,
    item_id: Annotated[int, Path(title="The ID of the item to get", ge=0, le=1000)],
    q: str,
    size: Annotated[float, Query(gt=0, lt=10.5)],
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})
    if size:
        results.update({"size": size})

pillow==11.0.0
# For image processing by Material for MkDocs
cairosvg==2.7.1
mkdocstrings[python]==0.26.1
griffe-typingdoc==0.2.7
# For griffe, it formats with black
black==24.3.0
mkdocs-macros-plugin==1.0.5

## 响应模型编码参数

你的响应模型可以具有默认值，例如：

```Python hl_lines="11  13-14"
{!../../docs_src/response_model/tutorial004.py!}
```

* `description: Union[str, None] = None` 具有默认值 `None`。
* `tax: float = 10.5` 具有默认值 `10.5`.
* `tags: List[str] = []` 具有一个空列表作为默认值： `[]`.

但如果它们并没有存储实际的值，你可能想从结果中忽略它们的默认值。

举个例子，当你在 NoSQL 数据库中保存了具有许多可选属性的模型，但你又不想发送充满默认值的很长的 JSON 响应。

### 使用 `response_model_exclude_unset` 参数

     * is to avoid unnecessary stalls in situations like this: A RateLimiter of 1qps, and 4 threads,
     * all calling acquire() at these moments:
     *
     * T0 at 0 seconds
     * T1 at 1.05 seconds
     * T2 at 2 seconds
     * T3 at 3 seconds
     *
     * Due to the slight delay of T1, T2 would have to sleep till 2.05 seconds, and T3 would also
     * have to sleep till 3.05 seconds.
     */

# For release jobs, we will pin these on the release branch
keras-nightly ~= 3.0.0.dev
tb-nightly ~= 2.18.0.a
# Test dependencies
grpcio >= 1.24.3, < 2.0
portpicker == 1.6.0
scipy == 1.11.3
requests >= 2.31.0
packaging==23.2
setuptools==70.0.0
jax==0.4.7
# The dependencies below are needed for TF wheel testing.
tensorflow-io-gcs-filesystem==0.37.1
libclang >= 13.0.0

app = FastAPI()


@app.get("/items/{item_id}")
async def read_items(
    *,
    item_id: int = Path(title="The ID of the item to get", ge=0, le=1000),
    q: str,
    size: float = Query(gt=0, lt=10.5),
):
    results = {"item_id": item_id}
    if q:
        results.update({"q": q})
    if size:
        results.update({"size": size})

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

das Eingabemodell nun den Defaultwert `"tax": 10.5` hat, weil Sie das bereits gespeicherte Attribut `"tax": 20.2` nicht mit übergeben haben.

Die Daten werden darum mit einem „neuen“ `tax`-Wert von `10.5` abgespeichert.

## Teilweises Ersetzen mit `PATCH`