* Then it returns the **response**.

/// note | Technical Details

If you have dependencies with `yield`, the exit code will run *after* the middleware.

If there were any background tasks (covered in the [Background Tasks](background-tasks.md){.internal-link target=_blank} section, you will see it later), they will run *after* all the middleware.

///

## Create a middleware { #create-a-middleware }

    public Set<K> keySet() {
      /*
       * We can't use StandardKeySet, as NavigableMapTestSuiteBuilder assumes that our keySet is a
       * NavigableSet. We test StandardKeySet in the superclass, so it's still covered.
       */
      return navigableKeySet();
    }

    @Override
    public Collection<V> values() {
      return new StandardValues();
    }

    @Override
    public String toString() {

     *
     * @param context the query context
     * @param termQuery the term query to convert
     * @param boost the boost value to apply
     * @return the converted QueryBuilder
     */
    protected QueryBuilder convertTermQuery(final QueryContext context, final TermQuery termQuery, final float boost) {

It would also mean that if you get data from the `Request` object directly (for example, read the body) it won't be validated, converted or documented (with OpenAPI, for the automatic API user interface) by FastAPI.

Although any other parameter declared normally (for example, the body with a Pydantic model) would still be validated, converted, annotated, etc.

But there are specific cases where it's useful to get the `Request` object.

                    "description": "A very nice Item",
                    "price": 35.4,
                    "tax": 3.2,
                },
            },
            "converted": {
                "summary": "An example with converted data",
                "description": "FastAPI can convert price `strings` to actual `numbers` automatically",
                "value": {
                    "name": "Bar",

from typing_extensions import Literal

if sys.version_info >= (3, 13):  # pragma: no cover
    from inspect import iscoroutinefunction
else:  # pragma: no cover
    from asyncio import iscoroutinefunction


def _unwrapped_call(call: Optional[Callable[..., Any]]) -> Any:
    if call is None:
        return call  # pragma: no cover
    unwrapped = inspect.unwrap(_impartial(call))
    return unwrapped

                                            "tax": 3.2,
                                        },
                                    },
                                    "converted": {
                                        "summary": "An example with converted data",
                                        "description": "FastAPI can convert price `strings` to actual `numbers` automatically",

    public WildcardQueryCommand() {
        super();
    }

    private static final Logger logger = LogManager.getLogger(WildcardQueryCommand.class);

    /**
     * Flag indicating whether wildcard terms should be converted to lowercase.
     */
    protected boolean lowercaseWildcard = true;

    @Override
    protected String getQueryClassName() {
        return WildcardQuery.class.getSimpleName();
    }

    @Override

        def read_items(id: list[Item]):
            pass  # pragma: no cover


def test_invalid_tuple():
    with pytest.raises(AssertionError):
        app = FastAPI()

        class Item(BaseModel):
            title: str

        @app.get("/items/{id}")
        def read_items(id: tuple[Item, Item]):
            pass  # pragma: no cover


def test_invalid_dict():
    with pytest.raises(AssertionError):

For example, you cannot put a Pydantic model in a `JSONResponse` without first converting it to a `dict` with all the data types (like `datetime`, `UUID`, etc) converted to JSON-compatible types.

For those cases, you can use the `jsonable_encoder` to convert your data before passing it to a response:

{* ../../docs_src/response_directly/tutorial001_py310.py hl[5:6,20:21] *}