"title": "The Foo ID Stealers",
            "description": "There goes my stealer",
        },
    )
    assert response.status_code == 409

These types that have internal types are called "**generic**" types. And it's possible to declare them, even with their internal types.

To declare those types and the internal types, you can use the standard Python module `typing`. It exists specifically to support these type hints.

#### Newer versions of Python

The syntax using `typing` is **compatible** with all versions, from Python 3.6 to the latest ones, including Python 3.9, Python 3.10, etc.

            "title": "The Foo ID Stealers",
            "description": "There goes my stealer",
        },
    )
    assert response.status_code == 400

If it doesn't see an `Authorization` header, or the value doesn't have a `Bearer ` token, it will respond with a 401 status code error (`UNAUTHORIZED`) directly.

You don't even have to check if the token exists to return an error. You can be sure that if your function is executed, it will have a `str` in that token.

You can try it already in the interactive docs:

<img src="/img/tutorial/security/image03.png">

```console
// Create an env var MY_NAME in line for this program call
$ MY_NAME="Wade Wilson" python main.py

// Now it can read the environment variable

Hello Wade Wilson from Python

// The env var no longer exists afterwards
$ python main.py

Hello World from Python
```

</div>

!!! tip
    👆 💪 ✍ 🌅 🔃 ⚫️ <a href="https://12factor.net/config" class="external-link" target="_blank">1️⃣2️⃣-⚖ 📱: 📁</a>.

            "title": "The Foo ID Stealers",
            "description": "There goes my stealer",
        },
    )
    assert response.status_code == 400

            "title": "The Foo ID Stealers",
            "description": "There goes my stealer",
        },
    )
    assert response.status_code == 409

```console
// Create an env var MY_NAME in line for this program call
$ MY_NAME="Wade Wilson" python main.py

// Now it can read the environment variable

Hello Wade Wilson from Python

// The env var no longer exists afterwards
$ python main.py

Hello World from Python
```

</div>

!!! tip

            "title": "The Foo ID Stealers",
            "description": "There goes my stealer",
        },
    )
    assert response.status_code == 400

# Templates

Você pode usar qualquer template engine com o **FastAPI**.

Uma escolha comum é o Jinja2, o mesmo usado pelo Flask e outras ferramentas.

Existem utilitários para configurá-lo facilmente que você pode usar diretamente em sua aplicação **FastAPI** (fornecidos pelo Starlette).

## Instalação de dependências

Para instalar o `jinja2`, siga o código abaixo:

<div class="termy">

```console
$ pip install jinja2
```