assert response.json() == {"name": "widget", "price": 9.99}


def test_ujson_response_emits_deprecation_warning():
    with pytest.warns(FastAPIDeprecationWarning, match="UJSONResponse is deprecated"):

    "and https://fastapi.tiangolo.com/tutorial/response-model/",
    category=FastAPIDeprecationWarning,
    stacklevel=2,
)
class UJSONResponse(JSONResponse):
    """JSON response using the ujson library to serialize data to JSON.

    **Deprecated**: `UJSONResponse` is deprecated. FastAPI now serializes data
    directly to JSON bytes via Pydantic when a return type or response model is

```python
from fastapi.responses import (
    FileResponse,
    HTMLResponse,
    JSONResponse,
    ORJSONResponse,
    PlainTextResponse,
    RedirectResponse,
    Response,
    StreamingResponse,
    UJSONResponse,
)
```

## FastAPI Responses

There were a couple of custom FastAPI response classes that were intended to optimize JSON performance.

from fastapi import FastAPI
from fastapi.responses import UJSONResponse

app = FastAPI()


@app.get("/items/", response_class=UJSONResponse)
async def read_items():