class CustomError(Exception):
    pass


@router.websocket("/custom_error/")
async def router_ws_custom_error(websocket: WebSocket):
    raise CustomError()


def make_app(app=None, **kwargs):
    app = app or FastAPI(**kwargs)
    app.include_router(router)
    app.include_router(prefix_router, prefix="/prefix")
    app.include_router(native_prefix_route)
    return app

      "gridPos": {
        "h": 4,
        "w": 8,
        "x": 0,
        "y": 4
      },
      "id": 12,
      "links": [],
      "maxDataPoints": 100,
      "options": {
        "colorMode": "none",
        "graphMode": "area",
        "justifyMode": "auto",
        "orientation": "horizontal",
        "reduceOptions": {
          "calcs": [
            "lastNotNull"
          ],

    summary: Optional[str] = None,
    description: Optional[str] = None,
    routes: Sequence[BaseRoute],
    webhooks: Optional[Sequence[BaseRoute]] = None,
    tags: Optional[List[Dict[str, Any]]] = None,
    servers: Optional[List[Dict[str, Union[str, Any]]]] = None,
    terms_of_service: Optional[str] = None,
    contact: Optional[Dict[str, Union[str, Any]]] = None,

//// tab | Python 3.10+

```Python hl_lines="7"
{!> ../../docs_src/query_params/tutorial002_py310.py!}
```

////

//// tab | Python 3.8+

```Python hl_lines="9"
{!> ../../docs_src/query_params/tutorial002.py!}
```

////

In this case, the function parameter `q` will be optional, and will be `None` by default.

/// check

{!> ../../docs_src/path_params_numeric_validations/tutorial001_an.py!}
```

////

//// tab | Python 3.10+ non-Annotated

/// tip

尽可能选择使用 `Annotated` 的版本。

///

```Python hl_lines="1"
{!> ../../docs_src/path_params_numeric_validations/tutorial001_py310.py!}
```

////

//// tab | Python 3.8+ non-Annotated

/// tip

尽可能选择使用 `Annotated` 的版本。

///

```Python hl_lines="3"

			return []string{"UNMATCHED"}
		}
	case *matcher.Matcher_OnMatch_Matcher:
		ms, f := recurse(fc.GetName(), v.Matcher)
		if !f {
			return []string{"NONE"}
		}
		return ms
	}
	ms, f := recurse(fc.GetName(), l.GetFilterChainMatcher())
	if !f {
		return []string{"NONE"}
	}
	return ms
}

func recurse(name string, match *matcher.Matcher) ([]string, bool) {
	switch v := match.GetOnNoMatch().GetOnMatch().(type) {

            // Filter out any non-public APIs
            f.exclude(PublicApi.INSTANCE.getExcludes());
        }));
        extension.getKotlinDslSource().from(sourcesPath.getIncoming().artifactView(v -> v.lenient(true)).getFiles().getAsFileTree().matching(f -> {
            f.include(PublicKotlinDslApi.INSTANCE.getIncludes());
            // Filter out any non-public APIs

Par exemple, le modèle ci-dessus déclare un "objet" JSON (ou `dict` Python) tel que :

```JSON
{
    "name": "Foo",
    "description": "An optional description",
    "price": 45.2,
    "tax": 3.5
}
```

...`description` et `tax` étant des attributs optionnels (avec `None` comme valeur par défaut), cet "objet" JSON serait aussi valide :

app = FastAPI()


class Item(BaseModel):
    name: str
    price: float
    is_offer: Union[bool, None] = None


@app.get("/")
def read_root():
    return {"Hello": "World"}


@app.get("/items/{item_id}")
def read_item(item_id: int, q: Union[str, None] = None):
    return {"item_id": item_id, "q": q}


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

 *  </tr>
 *  <tr>
 *      <td>implementation</td>
 *      <td>none (detected)</td>
 *      <td>Yes</td>
 *      <td>The Mojo's fully-qualified class name (or script path in the case of non-Java Mojos).</td>
 *  </tr>
 *  <tr>
 *      <td>language</td>
 *      <td>none (detected)</td>
 *      <td>No. Default: <code>java</code></td>