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

O `@app.get("/")` diz ao **FastAPI** que a função logo abaixo é responsável por tratar as requisições que vão para:

* a rota `/`
* usando o  <abbr title="o método HTTP GET">operador <code>get</code></abbr>

/// info | "`@decorador`"

Essa sintaxe `@alguma_coisa` em Python é chamada de "decorador".

* <a href="https://github.com/OAI/OpenAPI-Specification" class="external-link" target="_blank"><strong>OpenAPI</strong></a> for API creation, including declarations of <abbr title="also known as: endpoints, routes">path</abbr> <abbr title="also known as HTTP methods, as POST, GET, PUT, DELETE">operations</abbr>, parameters, request bodies, security, etc.

////

Örneğin, OAuth2 spesifikasyonunun kullanılabileceği ("şifre akışı" olarak adlandırılan) yollardan birinde, form alanları olarak <abbr title="Kullanıcı Adı: Username">"username"</abbr> ve <abbr title="Şifre: Password">"password"</abbr> gönderilmesi gerekir.

```

////

Zum Beispiel stellt eine der Möglichkeiten, die OAuth2 Spezifikation zu verwenden (genannt <abbr title='„Passwort-Fluss“'>„password flow“</abbr>), die Bedingung, einen `username` und ein `password` als Formularfelder zu senden.

Die <abbr title="Specification – Spezifikation">Spec</abbr> erfordert, dass die Felder exakt `username` und `password` genannt werden und als Formularfelder, nicht JSON, gesendet werden.

///

Entonces, deberías fijar la versión así:

```txt
fastapi>=0.45.0,<0.46.0
```

En versiones <abbr title="versiones menores">"MINOR"</abbr> son añadidas nuevas características y posibles <abbr title="Cambios que rompen posibles funcionalidades o compatibilidad">breaking changes</abbr>.

/// tip | Consejo

# <abbr title="En anglais: Debugging">Débogage</abbr>

Vous pouvez connecter le <abbr title="En anglais: debugger">débogueur</abbr> dans votre éditeur, par exemple avec Visual Studio Code ou PyCharm.

## Faites appel à `uvicorn`

Dans votre application FastAPI, importez et exécutez directement `uvicorn` :

{* ../../docs_src/debugging/tutorial001.py hl[1,15] *}

### À propos de `__name__ == "__main__"`

Coitados dos banners de cookies com todo o seu esforço para obter o seu consentimento para a <abbr title="Isso é uma outra piada. Não preste atenção em mim. Beba um café com o seu cookie. ☕">API rejeitá-lo</abbr>. 🍪

## 🔢 🔬: 🎈, 🌘 🌘 & 🌘 🌘

🔢 🔬 👷 `float` 💲.

📥 🌐❔ ⚫️ ▶️️ ⚠ 💪 📣 <abbr title="greater than"><code>gt</code></abbr> &amp; 🚫 <abbr title="greater than or equal"><code>ge</code></abbr>. ⏮️ ⚫️ 👆 💪 🚚, 🖼, 👈 💲 🔜 👑 🌘 `0`, 🚥 ⚫️ 🌘 🌘 `1`.

, `0.5` 🔜 ☑ 💲. ✋️ `0.0` ⚖️ `0` 🔜 🚫.

&amp; 🎏 <abbr title="less than"><code>lt</code></abbr>.

```Python hl_lines="11"

{!../../docs_src/path_params/tutorial002.py!}
```

👉 💼, `item_id` 📣 `int`.

/// check

👉 🔜 🤝 👆 👨‍🎨 🐕‍🦺 🔘 👆 🔢, ⏮️ ❌ ✅, 🛠️, ♒️.

///

## 💽 <abbr title="also known as: serialization, parsing, marshalling">🛠️</abbr>

🚥 👆 🏃 👉 🖼 &amp; 📂 👆 🖥 <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a>, 👆 🔜 👀 📨:

```JSON
{"item_id":3}
```

路径装饰器还支持 `summary` 和 `description` 这两个参数：

```Python hl_lines="20-21"
{!../../docs_src/path_operation_configuration/tutorial003.py!}
```

## 文档字符串（`docstring`）

描述内容比较长且占用多行时，可以在函数的 <abbr title="函数中作为第一个表达式，用于文档目的的一个多行字符串（并没有被分配个任何变量）">docstring</abbr> 中声明*路径操作*的描述，**FastAPI** 支持从文档字符串中读取描述内容。

文档字符串支持 <a href="https://en.wikipedia.org/wiki/Markdown" class="external-link" target="_blank">Markdown</a>，能正确解析和显示 Markdown 的内容，但要注意文档字符串的缩进。