```Python hl_lines="3  5-6"
{
    "name": "Baz",
    "description": None,
    "price": 50.2,
    "tax": 10.5,
    "tags": []
}
```

FastAPI is smart enough (actually, Pydantic is smart enough) to realize that, even though `description`, `tax`, and `tags` have the same values as the defaults, they were set explicitly (instead of taken from the defaults).

So, they will be included in the JSON response.

!!! tip

In this case, the original path `/app` would actually be served at `/api/v1/app`.

Even though all your code is written assuming there's just `/app`.

```Python hl_lines="6"
{!../../../docs_src/behind_a_proxy/tutorial001.py!}
```

    response = client.get(
        "/users/me", headers={"Authorization": f"Bearer {access_token}"}
    )
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not enough permissions"}
    assert response.headers["WWW-Authenticate"] == 'Bearer scope="me"'


def test_token_nonexistent_user():
    response = client.get(
        "/users/me",
        headers={

    response = client.get(
        "/users/me", headers={"Authorization": f"Bearer {access_token}"}
    )
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not enough permissions"}
    assert response.headers["WWW-Authenticate"] == 'Bearer scope="me"'


@needs_py39
def test_token_nonexistent_user(client: TestClient):
    response = client.get(
        "/users/me",

* **After** obtaining a secure connection, the communication protocol is **still HTTP**.
    * The contents are **encrypted**, even though they are being sent with the **HTTP protocol**.

In this case, it would be better to get **one extra server** and run some processes on it so that they all have **enough RAM and CPU time**.

    The `Union` in `Union[str, None]` will allow your editor to give you better support and detect errors.

## Additional validation

We are going to enforce that even though `q` is optional, whenever it is provided, **its length doesn't exceed 50 characters**.

### Import `Query` and `Annotated`

To achieve that, first import:

* `Query` from `fastapi`

### Reproduce the problem

For most of the cases and most of the questions there's something related to the person's **original code**.

In many cases they will only copy a fragment of the code, but that's not enough to **reproduce the problem**.

<img src="/img/async/concurrent-burgers/concurrent-burgers-02.png" class="illustration">

The cashier says something to the cook in the kitchen so they know they have to prepare your burgers (even though they are currently preparing the ones for the previous clients).

<img src="/img/async/concurrent-burgers/concurrent-burgers-03.png" class="illustration">

You pay. 💸

The cashier gives you the number of your turn.

    response = client.get(
        "/users/me", headers={"Authorization": f"Bearer {access_token}"}
    )
    assert response.status_code == 401, response.text
    assert response.json() == {"detail": "Not enough permissions"}
    assert response.headers["WWW-Authenticate"] == 'Bearer scope="me"'


def test_token_nonexistent_user():
    response = client.get(
        "/users/me",
        headers={