### Que sont les « Context Managers » { #what-are-context-managers }

Les « Context Managers » sont des objets Python que vous pouvez utiliser dans une instruction `with`.

Par exemple, [vous pouvez utiliser `with` pour lire un fichier](https://docs.python.org/3/tutorial/inputoutput.html#reading-and-writing-files) :

```Python
with open("./somefile.txt") as f:
    contents = f.read()
    print(contents)
```

///

### Activer les en-têtes transférés par le proxy { #enable-proxy-forwarded-headers }

Vous pouvez démarrer FastAPI CLI avec l'option de CLI `--forwarded-allow-ips` et fournir les adresses IP à considérer comme fiables pour lire ces en‑têtes transférés.

Si vous la définissez à `--forwarded-allow-ips="*"`, elle fera confiance à toutes les IP entrantes.

# Перші кроки { #first-steps }

Найпростіший файл FastAPI може виглядати так:

{* ../../docs_src/first_steps/tutorial001_py310.py *}

Скопіюйте це до файлу `main.py`.

Запустіть live-сервер:

<div class="termy">

```console
$ <font color="#4E9A06">fastapi</font> dev

  <span style="background-color:#009485"><font color="#D3D7CF"> FastAPI </font></span>  Starting development server 🚀

Usa el chat solo para otras conversaciones generales.

///

### No uses el chat para preguntas { #dont-use-the-chat-for-questions }

Ten en cuenta que dado que los chats permiten una "conversación más libre", es fácil hacer preguntas que son demasiado generales y más difíciles de responder, por lo que es posible que no recibas respuestas.

## Servidores adicionales { #additional-servers }

/// warning | Advertencia

Este es un caso de uso más avanzado. Siéntete libre de omitirlo.

///

Por defecto, **FastAPI** creará un `server` en el esquema de OpenAPI con la URL para el `root_path`.

(It's not a subtraction, just idiosyncratic syntax.)
The frame size <code>$24-8</code> states that the function has a 24-byte frame
and is called with 8 bytes of argument, which live on the caller's frame.
If <code>NOSPLIT</code> is not specified for the <code>TEXT</code>,
the argument size must be provided.
For assembly functions with Go prototypes, <code>go</code> <code>vet</code> will check that the

Now, let's see the module at `app/main.py`.

Here's where you import and use the class `FastAPI`.

This will be the main file in your application that ties everything together.

And as most of your logic will now live in its own specific module, the main file will be quite simple.

### Import `FastAPI` { #import-fastapi }

You import and create a `FastAPI` class as normally.

    of the contribution must be compared against the cost of maintaining the
    feature.
*   Full new features (e.g., a new op implementing a cutting-edge algorithm)
    typically will live in
    [tensorflow/addons](https://github.com/tensorflow/addons) to get some
    airtime before a decision is made regarding whether they are to be migrated
    to the core.

against each other; however, they got settled down in a minute or
two, and the game began.  Alice thought she had never seen such a
curious croquet-ground in her life; it was all ridges and
furrows; the balls were live hedgehogs, the mallets live
flamingoes, and the soldiers had to double themselves up and to
stand on their hands and feet, to make the arches.

  The chief difficulty Alice found at first was in managing her

C'est pourquoi, dans cet exemple, nous devons le déclarer dans le paramètre `response_model`.

... mais continuez à lire ci-dessous pour voir comment contourner cela.

## Type de retour et filtrage des données { #return-type-and-data-filtering }