assert response.status_code == 200, response.text
    assert response.json() == {"p": None}


@pytest.mark.parametrize(
    "path",
    ["/optional-str", "/model-optional-str"],
)
def test_optional_str(path: str):
    client = TestClient(app)
    response = client.post(path, json={"p": "hello"})
    assert response.status_code == 200
    assert response.json() == {"p": "hello"}