<title>Script blocks</title>
            <para>No script blocks</para>
        </section>
    </chapter>
</root>'''
    }

    def rendersKnownSubtypes() {
        def sourceContent = parse('''
            <chapter>
                <section><title>Properties</title></section>
            </chapter>
        ''')

# Simple OAuth2 with Password and Bearer

Now let's build from the previous chapter and add the missing parts to have a complete security flow.

## Get the `username` and `password`

We are going to use **FastAPI** security utilities to get the `username` and `password`.

OAuth2 specifies that when using the "password flow" (that we are using) the client/user must send a `username` and `password` fields as form data.

   *
   * <p><i>Notes:</i> This is an implementation of the algorithm for Lexicographical Permutations
   * Generation, described in Knuth's "The Art of Computer Programming", Volume 4, Chapter 7,
   * Section 7.2.1.2. The iteration order follows the lexicographical order. This means that the
   * first permutation will be in ascending order, and the last will be in descending order.
   *

In the next chapters, I'll give you more **concrete recipes** to deploy FastAPI applications.

But for now, let's check these important **conceptual ideas**. These concepts also apply to any other type of web API. 💡

## Security - HTTPS

   *
   * <p><i>Notes:</i> This is an implementation of the algorithm for Lexicographical Permutations
   * Generation, described in Knuth's "The Art of Computer Programming", Volume 4, Chapter 7,
   * Section 7.2.1.2. The iteration order follows the lexicographical order. This means that the
   * first permutation will be in ascending order, and the last will be in descending order.
   *

This code is something you can actually use in your application, save the password hashes in your database, etc.

We are going to start from where we left in the previous chapter and increment it.

## About JWT

JWT means "JSON Web Tokens".

It's a standard to codify a JSON object in a long dense string without spaces. It looks like this:

```

But even if you never use **FastAPI**, you would benefit from learning a bit about them.

/// note

If you are a Python expert, and you already know everything about type hints, skip to the next chapter.

///

## Motivation

Let's start with a simple example:

{* ../../docs_src/python_types/tutorial001.py *}

Calling this program outputs:

```
John Doe
```

En déclarant les types de vos variables, cela permet aux différents outils comme les éditeurs de texte d'offrir un meilleur support.

Ce chapitre n'est qu'un **tutoriel rapide / rappel** sur les annotations de type Python.
Seulement le minimum nécessaire pour les utiliser avec **FastAPI** sera couvert... ce qui est en réalité très peu.

        // will include a tag and length header as a prefix.
        val adapter = chooser(writer.typeHint) as DerAdapter<Any?>?
        when {
          adapter != null -> adapter.toDer(writer, value)
          else -> writer.writeOctetString(value as ByteString)
        }
      }

      override fun fromDer(reader: DerReader): Any? {
        val adapter = chooser(reader.typeHint) as DerAdapter<Any?>?
        return when {

    val sequenceOf = listOf(7L, 8L, 9L)
    val adapter = Adapters.INTEGER_AS_LONG.asSequenceOf()
    assertThat(adapter.fromDer(bytes)).isEqualTo(sequenceOf)
    assertThat(adapter.toDer(sequenceOf)).isEqualTo(bytes)
  }

  @Test fun `point with only x set`() {
    val bytes = "3003800109".decodeHex()
    val point = Point(9L, null)
    assertThat(Point.ADAPTER.fromDer(bytes)).isEqualTo(point)