FastAPI uses a **unique ID** for each *path operation*, it is used for the **operation ID** and also for the names of any needed custom models, for requests or responses.

You can customize that function. It takes an `APIRoute` and outputs a string.

For example, here it is using the first tag (you will probably have only one tag) and the *path operation* name (the function name).

#### 🔬 *➡ 🛠️ 👨‍🎨*

```Python hl_lines="6"
{!../../../docs_src/first_steps/tutorial001.py!}
```

`@app.get("/")` 💬 **FastAPI** 👈 🔢 ▶️️ 🔛 🈚 🚚 📨 👈 🚶:

* ➡ `/`
* ⚙️ <abbr title="an HTTP GET method"><code>get</code> 🛠️</abbr>

!!! info "`@decorator` ℹ"
    👈 `@something` ❕ 🐍 🤙 "👨‍🎨".

    👆 🚮 ⚫️ 🔛 🔝 🔢. 💖 📶 📔 👒 (👤 💭 👈 🌐❔ ⚖ 👟 ⚪️➡️).

     "👨‍🎨" ✊ 🔢 🔛 &amp; 🔨 🕳 ⏮️ ⚫️.

「**オペレーションズ**」とも呼ぶことにします。

#### *パスオペレーションデコレータ*を定義

```Python hl_lines="6"
{!../../../docs_src/first_steps/tutorial001.py!}
```
`@app.get("/")`は直下の関数が下記のリクエストの処理を担当することを**FastAPI**に伝えます:

* パス `/`
* <abbr title="an HTTP GET method"><code>get</code> オペレーション</abbr>

!!! info "`@decorator` について"
    Pythonにおける`@something`シンタックスはデコレータと呼ばれます。

    「デコレータ」は関数の上に置きます。かわいらしい装飾的な帽子のようです（この用語の由来はそこにあると思います）。

    {!> ../../../docs_src/query_params_str_validations/tutorial003_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="10"
    {!> ../../../docs_src/query_params_str_validations/tutorial003_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="11"
    {!> ../../../docs_src/query_params_str_validations/tutorial003_an.py!}
    ```

=== "Python 3.10+ nicht annotiert"

    {!> ../../../docs_src/query_params_str_validations/tutorial003_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="10"
    {!> ../../../docs_src/query_params_str_validations/tutorial003_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="11"
    {!> ../../../docs_src/query_params_str_validations/tutorial003_an.py!}
    ```

=== "Python 3.10+ без Annotated"

    ```Python hl_lines="3"
    {!> ../../../docs_src/header_params/tutorial001_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="3"
    {!> ../../../docs_src/header_params/tutorial001_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="3"
    {!> ../../../docs_src/header_params/tutorial001_an.py!}
    ```

=== "Python 3.10+ без Annotated"

    !!! tip "Подсказка"

"docs_src/dependencies/tutorial008_an.py" = ["F821"]
"docs_src/dependencies/tutorial008_an_py39.py" = ["F821"]
"docs_src/query_params_str_validations/tutorial012_an.py" = ["B006"]
"docs_src/query_params_str_validations/tutorial012_an_py39.py" = ["B006"]
"docs_src/query_params_str_validations/tutorial013_an.py" = ["B006"]
"docs_src/query_params_str_validations/tutorial013_an_py39.py" = ["B006"]

    {!> ../../../docs_src/path_params_numeric_validations/tutorial001_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="1  3"
    {!> ../../../docs_src/path_params_numeric_validations/tutorial001_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="3-4"
    {!> ../../../docs_src/path_params_numeric_validations/tutorial001_an.py!}
    ```

=== "Python 3.10+ nicht annotiert"

    ```Python hl_lines="8-9"
    {!> ../../../docs_src/dependencies/tutorial001_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="8-11"
    {!> ../../../docs_src/dependencies/tutorial001_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="9-12"
    {!> ../../../docs_src/dependencies/tutorial001_an.py!}
    ```

=== "Python 3.10+ nicht annotiert"

    !!! tip "Tipp"

    ```Python hl_lines="3"
    {!> ../../../docs_src/header_params/tutorial001_an_py310.py!}
    ```

=== "Python 3.9+"

    ```Python hl_lines="3"
    {!> ../../../docs_src/header_params/tutorial001_an_py39.py!}
    ```

=== "Python 3.8+"

    ```Python hl_lines="3"
    {!> ../../../docs_src/header_params/tutorial001_an.py!}
    ```

=== "Python 3.10+ non-Annotated"

    !!! tip