You could also use it to generate code automatically, for clients that communicate with your API. For example, frontend, mobile or IoT applications.

## Recap, step by step

### Step 1: import `FastAPI`

```Python hl_lines="1"
{!../../../docs_src/first_steps/tutorial001.py!}
```

`FastAPI` is a Python class that provides all the functionality for your API.

!!! note "Technical Details"

---

`async def`の代わりに通常の関数として定義することもできます:

```Python hl_lines="7"
{!../../../docs_src/first_steps/tutorial003.py!}
```

!!! note "備考"
    違いが分からない場合は、[Async: *"急いでいますか？"*](../async.md#_1){.internal-link target=_blank}を確認してください。

### Step 5: コンテンツの返信

```Python hl_lines="8"
{!../../../docs_src/first_steps/tutorial001.py!}
```

`dict`、`list`、`str`、`int`などを返すことができます。

```Python hl_lines="7"
{!../../../docs_src/first_steps/tutorial001.py!}
```

Это обычная Python функция.

**FastAPI** будет вызывать её каждый раз при получении `GET` запроса к URL "`/`".

В данном случае это асинхронная функция.

---

Вы также можете определить ее как обычную функцию вместо `async def`:

```Python hl_lines="7"
{!../../../docs_src/first_steps/tutorial003.py!}
```

```Python hl_lines="7"
{!../../../docs_src/first_steps/tutorial003.py!}
```

!!! note "Hinweis"
    Wenn Sie den Unterschied nicht kennen, lesen Sie [Async: *„In Eile?“*](../async.md#in-eile){.internal-link target=_blank}.

### Schritt 5: den Inhalt zurückgeben

```Python hl_lines="8"
{!../../../docs_src/first_steps/tutorial001.py!}
```

```Python hl_lines="1"
{!../../../docs_src/first_steps/tutorial001.py!}
```

`FastAPI` 🐍 🎓 👈 🚚 🌐 🛠️ 👆 🛠️.

!!! note "📡 ℹ"
    `FastAPI` 🎓 👈 😖 🔗 ⚪️➡️ `Starlette`.

    👆 💪 ⚙️ 🌐 <a href="https://www.starlette.io/" class="external-link" target="_blank">💃</a> 🛠️ ⏮️ `FastAPI` 💁‍♂️.

### 🔁 2️⃣: ✍ `FastAPI` "👐"

```Python hl_lines="3"
{!../../../docs_src/first_steps/tutorial001.py!}
```

* Testes _backend_ _REST_ baseados no **Pytest**, integrados com Docker, então você pode testar a interação completa da API, independente do banco de dados. Como roda no Docker, ele pode construir um novo repositório de dados do zero toda vez (assim você pode usar ElasticSearch, MongoDB, CouchDB, ou o que quiser, e apenas testar que a API esteja funcionando).

## Let's Encrypt

Antes de Let's Encrypt, esses certificados HTTPS eram vendidos por terceiros confiáveis.

    ```

    </div>

If it shows the `pip` binary at `env/bin/pip` then it worked. 🎉

Make sure you have the latest pip version on your local environment to avoid errors on the next steps:

<div class="termy">

```console
$ python -m pip install --upgrade pip

---> 100%
```

</div>

!!! tip

      - master
  pull_request:
    types:
      - opened
      - synchronize
  schedule:
    # cron every week on monday
    - cron: "0 0 * * 1"

jobs:
  lint:
    runs-on: ubuntu-latest
    steps:
      - name: Dump GitHub context
        env:
          GITHUB_CONTEXT: ${{ toJson(github) }}
        run: echo "$GITHUB_CONTEXT"
      - uses: actions/checkout@v4
      - name: Set up Python

    * Entonces, al usar FastAPI estás ahorrando tiempo de desarrollo, errores, líneas de código y probablemente obtendrías el mismo rendimiento (o mejor) que obtendrías si no lo usaras (ya que tendrías que implementarlo todo en tu código).