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.

        Doc(
            """
            'Whitelist' validation step. The parameter field will be the single one
            allowed by the alias or set of aliases defined.
            """
        ),
    ] = None,
    serialization_alias: Annotated[
        Union[str, None],
        Doc(
            """
            'Blacklist' validation step. The vanilla parameter field will be the

## ステップ毎の要約

### Step 1: `FastAPI`をインポート

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

`FastAPI`は、APIのすべての機能を提供するPythonクラスです。

!!! note "技術詳細"
    `FastAPI`は`Starlette`を直接継承するクラスです。

    `FastAPI`でも<a href="https://www.starlette.io/" class="external-link" target="_blank">Starlette</a>のすべての機能を利用可能です。

### Step 2: `FastAPI`の「インスタンス」を生成

Let's say you want to add translations for Creole, and it's not yet there in the docs.

Checking the link from above, the code for "Creole" is `ht`.

The next step is to run the script to generate a new translation directory:

<div class="termy">

```console
// Use the command new-lang, pass the language code as a CLI argument
$ python ./scripts/docs.py new-lang ht

It used custom types in its declarations instead of standard Python types, but it was still a huge step forward.

It also was one of the first frameworks to generate a custom schema declaring the whole API in JSON.

# About HTTPS

It is easy to assume that HTTPS is something that is just "enabled" or not.

But it is way more complex than that.

!!! tip
    If you are in a hurry or don't care, continue with the next sections for step by step instructions to set everything up with different techniques.

To **learn the basics of HTTPS**, from a consumer perspective, check <a href="https://howhttps.works/" class="external-link" target="_blank">https://howhttps.works/</a>.

# 关于 HTTPS

人们很容易认为 HTTPS 仅仅是“启用”或“未启用”的东西。

但实际情况比这复杂得多。

!!!提示
     如果你很赶时间或不在乎，请继续阅读下一部分，下一部分会提供一个step-by-step的教程，告诉你怎么使用不同技术来把一切都配置好。

要从用户的视角**了解 HTTPS 的基础知识**，请查看 <a href="https://howhttps.works/" class="external-link" target="_blank">https://howhttps.works/</a>。

现在，从**开发人员的视角**，在了解 HTTPS 时需要记住以下几点：

* 要使用 HTTPS，**服务器**需要拥有由**第三方**生成的**"证书(certificate)"**。
     * 这些证书实际上是从第三方**获取**的，而不是“生成”的。
* 证书有**生命周期**。
     * 它们会**过期**。

* 🌐 Remove Vietnamese note about missing translation. PR [#9957](https://github.com/tiangolo/fastapi/pull/9957) by [@tiangolo](https://github.com/tiangolo).

### Internal

* 👷 Add GitHub Actions step dump context to debug external failures. PR [#10008](https://github.com/tiangolo/fastapi/pull/10008) by [@tiangolo](https://github.com/tiangolo).

In an advanced scenario where you know you need the dependency to be called at every step (possibly multiple times) in the same request instead of using the "cached" value, you can set the parameter `use_cache=False` when using `Depends`:

=== "Python 3.8+"

    ```Python hl_lines="1"

In the end, a hierarchical tree of dependencies is built, and the **Dependency Injection** system takes care of solving all these dependencies for you (and their sub-dependencies) and providing (injecting) the results at each step.

For example, let's say you have 4 API endpoints (*path operations*):

* `/items/public/`
* `/items/private/`
* `/users/{user_id}/activate`
* `/items/pro/`