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.

Inclus des librairies externes basées, aussi, sur Pydantic, servent d'<abbr title="Object-Relational Mapper">ORM</abbr>s, <abbr title="Object-Document Mapper">ODM</abbr>s pour les bases de données.

```Python hl_lines="7"
{!../../../docs_src/query_params_str_validations/tutorial005.py!}
```

!!! note "Rappel"
    Avoir une valeur par défaut rend le paramètre optionnel.

## Rendre ce paramètre requis

Bunlara Pydantic üzerine kurulu <abbr title="Object-Relational Mapper">ORM</abbr> databaseler ve , <abbr title="Object-Document Mapper">ODM</abbr> kütüphaneler de dahil olmak üzere.

!!! tip
    The `shutdown` would happen when you are **stopping** the application.

    Maybe you need to start a new version, or you just got tired of running it. 🤷

### Lifespan function

If you catch an exception using `except` in a dependency with `yield` and you don't raise it again (or raise a new exception), FastAPI won't be able to notice there was an exception, the same way that would happen with regular Python:

=== "Python 3.9+"

    ```Python hl_lines="15-16"
    {!> ../../../docs_src/dependencies/tutorial008c_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="14-15"

Hey! 👋

Das bin ich:

{% if people %}
<div class="user-list user-list-center">
{% for user in people.maintainers %}

<div class="user"><a href="{{ user.url }}" target="_blank"><div class="avatar-wrapper"><img src="{{ user.avatarUrl }}"/></div><div class="title">@{{ user.login }}</div></a> <div class="count">Answers: {{ user.answers }}</div><div class="count">Pull Requests: {{ user.prs }}</div></div>
{% endfor %}

</div>

Привіт! 👋

Це я:

{% if people %}
<div class="user-list user-list-center">
{% for user in people.maintainers %}

<div class="user"><a href="{{ user.url }}" target="_blank"><div class="avatar-wrapper"><img src="{{ user.avatarUrl }}"/></div><div class="title">@{{ user.login }}</div></a> <div class="count">Answers: {{ user.answers }}</div><div class="count">Pull Requests: {{ user.prs }}</div></div>
{% endfor %}

</div>

Ei! 👋

Este sou eu:

{% if people %}
<div class="user-list user-list-center">
{% for user in people.maintainers %}

<div class="user"><a href="{{ user.url }}" target="_blank"><div class="avatar-wrapper"><img src="{{ user.avatarUrl }}"/></div><div class="title">@{{ user.login }}</div></a> <div class="count">Respostas: {{ user.answers }}</div><div class="count">Pull Requests: {{ user.prs }}</div></div>
{% endfor %}

</div>

Wliczając w to zewnętrzne biblioteki, również oparte o Pydantic, takie jak <abbr title="Mapowanie obiektowo-relacyjne. Po angielsku: Object-Relational Mapper">ORM</abbr>, <abbr title="Object-Document Mapper">ODM</abbr> dla baz danych.

Oznacza to, że w wielu przypadkach możesz przekazać ten sam obiekt, który otrzymasz z żądania **bezpośrednio do bazy danych**, ponieważ wszystko jest walidowane automatycznie.