default_response_class=ResponseLevel1,
    callbacks=callback_router1.routes,
)

app.include_router(router2_override)

app.include_router(router2_default)

client = TestClient(app)


def test_level1_override():
    response = client.get("/override1?level1=foo")
    assert response.json() == "foo"
    assert response.headers["content-type"] == "application/x-level-1"
    assert "x-level0" in response.headers

* 🔧 Fix Ruff configuration unintentionally enabling and re-disabling mccabe complexity check. PR [#10893](https://github.com/tiangolo/fastapi/pull/10893) by [@jiridanek](https://github.com/jiridanek).
* ✅ Re-enable test in `tests/test_tutorial/test_header_params/test_tutorial003.py` after fix in Starlette. PR [#10904](https://github.com/tiangolo/fastapi/pull/10904) by [@ooknimm](https://github.com/ooknimm).

### Docs