from starlette.responses import StreamingResponse as StreamingResponse  # noqa

try:
    import ujson
except ImportError:  # pragma: nocover
    ujson = None  # type: ignore


try:
    import orjson
except ImportError:  # pragma: nocover
    orjson = None  # type: ignore


class UJSONResponse(JSONResponse):
    """
    JSON response using the high-performance ujson library to serialize data to JSON.

client = TestClient(app)


@pytest.mark.parametrize(
    "path,headers,expected_status,expected_response",
    [
        ("/items", None, 200, {"strange_header": None}),
        ("/items", {"X-Header": "notvalid"}, 200, {"strange_header": None}),
        (
            "/items",
            {"strange_header": "FastAPI test"},
            200,
            {"strange_header": "FastAPI test"},
        ),

    return client


@needs_py39
@pytest.mark.parametrize(
    "path,headers,expected_status,expected_response",
    [
        ("/items", None, 200, {"strange_header": None}),
        ("/items", {"X-Header": "notvalid"}, 200, {"strange_header": None}),
        (
            "/items",
            {"strange_header": "FastAPI test"},
            200,
            {"strange_header": "FastAPI test"},
        ),

    return client


@needs_py310
@pytest.mark.parametrize(
    "path,headers,expected_status,expected_response",
    [
        ("/items", None, 200, {"strange_header": None}),
        ("/items", {"X-Header": "notvalid"}, 200, {"strange_header": None}),
        (
            "/items",
            {"strange_header": "FastAPI test"},
            200,
            {"strange_header": "FastAPI test"},
        ),

                            && !conn.getNegotiateResponse().isSigningRequired() ) {
                        // if signing is not enforced, dont use connections that have signing enforced
                        // for purposes that dont require it.
                        if ( log.isTraceEnabled() ) {
                            log.debug("Cannot reuse, signing enforced on connection " + conn);

        "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
    assert response.json() == {
        "name": "Foo",
        "price": 50.5,
        "description": None,
        "tax": None,
    }

        "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
    assert response.json() == {
        "name": "Foo",
        "price": 50.5,
        "description": None,
        "tax": None,
    }


@needs_py310

        "item_id": 5,
        "item": {
            "name": "Foo",
            "price": 50.5,
            "description": None,
            "tax": None,
        },
        "q": "bar",
    }


@needs_py310
def test_post_no_body_q_bar(client: TestClient):
    response = client.put("/items/5?q=bar", json=None)
    assert response.status_code == 200
    assert response.json() == {"item_id": 5, "q": "bar"}


@needs_py310

        "item_id": 5,
        "item": {
            "name": "Foo",
            "price": 50.5,
            "description": None,
            "tax": None,
        },
        "q": "bar",
    }


def test_post_no_body_q_bar(client: TestClient):
    response = client.put("/items/5?q=bar", json=None)
    assert response.status_code == 200
    assert response.json() == {"item_id": 5, "q": "bar"}

```

デフォルト値`None`を`Query(default=None)`に置き換える必要があるので、`Query`の最初の引数はデフォルト値を定義するのと同じです。

なので:

```Python
q: Optional[str] = Query(default=None)
```

...を以下と同じようにパラメータをオプションにします:

```Python
q: Optional[str] = None
```

しかし、これはクエリパラメータとして明示的に宣言しています。

/// info | "情報"

FastAPIは以下の部分を気にすることを覚えておいてください:

```Python
= None
```

もしくは:

```Python