## Program and Process

We will talk a lot about the running "**process**", so it's useful to have clarity about what it means, and what's the difference with the word "**program**".

### What is a Program

The word **program** is commonly used to describe many things:

* The **code** that you write, the **Python files**.

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

* 🚨 Avoid using `Optional[SomeType]`
* Instead ✨ **use `Union[SomeType, None]`** ✨.

Both are equivalent and underneath they are the same, but I would recommend `Union` instead of `Optional` because the word "**optional**" would seem to imply that the value is optional, and it actually means "it can be `None`", even if it's not optional and is still required.

I think `Union[SomeType, None]` is more explicit about what it means.

* ✏ Fix typo about file path in `docs/en/docs/tutorial/bigger-applications.md`. PR [#3285](https://github.com/tiangolo/fastapi/pull/3285) by [@HolyDorus](https://github.com/HolyDorus).
* ✏ Re-word to clarify test client in `docs/en/docs/tutorial/testing.md`. PR [#3382](https://github.com/tiangolo/fastapi/pull/3382) by [@Bharat123rox](https://github.com/Bharat123rox).

Because this code is executed before the application **starts** taking requests, and right after it **finishes** handling requests, it covers the whole application **lifespan** (the word "lifespan" will be important in a second 😉).

クエリパラメータ`q`を`Query`やデフォルト値なしで宣言し、パスパラメータ`item_id`を`Path`を用いて宣言し、それらを別の順番に並びたい場合、Pythonには少し特殊な構文が用意されています。

関数の最初のパラメータとして`*`を渡します。

Pythonはその`*`で何かをすることはありませんが、それ以降のすべてのパラメータがキーワード引数（キーと値のペア）として呼ばれるべきものであると知っているでしょう。それは<abbr title="From: K-ey W-ord Arg-uments"><code>kwargs</code></abbr>としても知られています。たとえデフォルト値がなくても。

```Python hl_lines="8"
{!../../../docs_src/path_params_numeric_validations/tutorial003.py!}
```

## 数値の検証: 以上

Pass `*`, as the first parameter of the function.

Python won't do anything with that `*`, but it will know that all the following parameters should be called as keyword arguments (key-value pairs), also known as <abbr title="From: K-ey W-ord Arg-uments"><code>kwargs</code></abbr>. Even if they don't have a default value.

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

### Better with `Annotated`

## Server Machine and Server Program

There's a small detail about names to keep in mind. 💡

The word "**server**" is commonly used to refer to both the remote/cloud computer (the physical or virtual machine) and also the program that is running on that machine (e.g. Uvicorn).

🚶‍♀️ `*`, 🥇 🔢 🔢.

🐍 🏆 🚫 🕳 ⏮️ 👈 `*`, ✋️ ⚫️ 🔜 💭 👈 🌐 📄 🔢 🔜 🤙 🇨🇻 ❌ (🔑-💲 👫), 💭 <abbr title="From: K-ey W-ord Arg-uments"><code>kwargs</code></abbr>. 🚥 👫 🚫 ✔️ 🔢 💲.

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

## 🔢 🔬: 👑 🌘 ⚖️ 🌓

### Preprocess the OpenAPI Specification for the Client Generator

The generated code still has some **duplicated information**.

We already know that this method is related to the **items** because that word is in the `ItemsService` (taken from the tag), but we still have the tag name prefixed in the method name too. 😕

We will probably still want to keep it for OpenAPI in general, as that will ensure that the operation IDs are **unique**.