assert response.json() == "foo"
    assert response.headers["content-type"] == "application/x-level-1"
    assert "x-level0" in response.headers
    assert "x-level1" in response.headers
    assert "x-level2" not in response.headers
    assert "x-level3" not in response.headers
    assert "x-level4" not in response.headers
    assert "x-level5" not in response.headers


def test_level1_default():

    String API_JSON_RESPONSE_HEADERS = "api.json.response.headers";

    /** The key of the configuration. e.g. false */
    String API_JSON_RESPONSE_EXCEPTION_INCLUDED = "api.json.response.exception.included";

    /** The key of the configuration. e.g.  */
    String API_GSA_RESPONSE_HEADERS = "api.gsa.response.headers";

    /** The key of the configuration. e.g. false */

    save_data: bool
    if_modified_since: str | None = None
    traceparent: str | None = None
    x_tag: list[str] = []


@app.get("/items/")
async def read_items(headers: Annotated[CommonHeaders, Header()]):
    return headers
```

Read the new docs: [Header Parameter Models](https://fastapi.tiangolo.com/tutorial/header-param-models/).

#### `Cookie` Parameter Models