def get_client(mod: ModuleType):
    client = TestClient(mod.app)
    client.headers.clear()
    return client


def test_get(client: TestClient):
    response = client.post(
        "/invoices/", json={"id": "fooinvoice", "customer": "John", "total": 5.3}
    )
    assert response.status_code == 200, response.text
    assert response.json() == {"msg": "Invoice received"}


def test_dummy_callback(mod: ModuleType):