And it can also be used by yourself, to debug, check and test the same application.

## The `password` flow

Now let's go back a bit and understand what is all that.

The `password` "flow" is one of the ways ("flows") defined in OAuth2, to handle security and authentication.

OAuth2 was designed so that the backend or API could be independent of the server that authenticates the user.

.screenshot:before {
  content: '';
  position: absolute;
  top: 15px;
  left: 15px;
  display: inline-block;
  width: 15px;
  height: 15px;
  border-radius: 50%;
  /* A little hack to display the window buttons in one pseudo element. */
  background: #d9515d;
  -webkit-box-shadow: 25px 0 0 #f4c025, 50px 0 0 #3ec930;
          box-shadow: 25px 0 0 #f4c025, 50px 0 0 #3ec930;

---> 100%
```

</div>

<a href="https://github.com/mpdavis/python-jose" class="external-link" target="_blank">Python-jose</a> requires a cryptographic backend as an extra.

Here we are using the recommended one: <a href="https://cryptography.io/" class="external-link" target="_blank">pyca/cryptography</a>.

!!! tip
    This tutorial previously used <a href="https://pyjwt.readthedocs.io/" class="external-link" target="_blank">PyJWT</a>.

    comment_id: Union[str, None] = None,
    body: Union[str, None] = None,
) -> Dict[str, Any]:
    headers = {"Authorization": f"token {settings.input_token.get_secret_value()}"}
    # some fields are only used by one query, but GraphQL allows unused variables, so
    # keep them here for simplicity
    variables = {
        "after": after,
        "category_id": category_id,
        "discussion_number": discussion_number,

{!../../../docs_src/nosql_databases/tutorial001.py!}
```

!!! note
    Notice that we have a `hashed_password` and a `type` field that will be stored in the database.

    But it is not part of the general `User` model (the one we will return in the *path operation*).

## Get the user

Now create a function that will:

* Take a username.
* Generate a document ID from it.
* Get the document with that ID.

{!../../../docs_src/metadata/tutorial001_1.py!}
```

## Metadata for tags

You can also add additional metadata for the different tags used to group your path operations with the parameter `openapi_tags`.

It takes a list containing one dictionary for each tag.

Each dictionary can contain:

* `name` (**required**): a `str` with the same tag name you use in the `tags` parameter in your *path operations* and `APIRouter`s.

    ```

=== "Python 3.8+"

    ```Python hl_lines="22"
    {!> ../../../docs_src/body_multiple_params/tutorial002.py!}
    ```

In this case, **FastAPI** will notice that there are more than one body parameters in the function (two parameters that are Pydantic models).

So, it will then use the parameter names as keys (field names) in the body, and expect a body like:

```JSON
{
    "item": {

{% if people %}
<div class="user-list user-list-center">
{% for user in people.one_year_experts[:20] %}

```

* Você deve ter uma estrutura de diretórios assim:

```
.
├── app
│   └── main.py
└── Dockerfile
```

### Construa a imagem Docker

* Vá para o diretório do projeto (onde seu `Dockerfile` está, contendo seu diretório `app`.
* Construa sua imagem FastAPI:

<div class="termy">

```console
$ docker build -t myimage .

---> 100%
```

</div>

---

"_If you're looking to learn one **modern framework** for building REST APIs, check out **FastAPI** [...] It's fast, easy to use and easy to learn [...]_"

"_We've switched over to **FastAPI** for our **APIs** [...] I think you'll like it [...]_"