## 의존성으로서의 클래스

파이썬 클래스의 인스턴스를 생성하기 위해 사용하는 것과 동일한 문법을 사용한다는 걸 알 수 있습니다.

예를 들어:

```Python
class Cat:
    def __init__(self, name: str):
        self.name = name


fluffy = Cat(name="Mr Fluffy")
```

이 경우에 `fluffy`는 클래스 `Cat`의 인스턴스입니다. 그리고 우리는 `fluffy`를 만들기 위해서 `Cat`을 "호출"했습니다.

따라서, 파이썬 클래스는 **호출 가능**합니다.

그래서 **FastAPI**에서는 파이썬 클래스를 의존성으로 사용할 수 있습니다.

```
https://yourapi.com/invoices/?callback_url=https://www.external.org/events
```

com um corpo JSON de:

```JSON
{
    "id": "2expen51ve",
    "customer": "Mr. Richie Rich",
    "total": "9999"
}
```

então *sua API* processará a fatura e, em algum momento posterior, enviará um request de callback para o `callback_url` (a *API externa*):

```

        function ->> execute: execute function code
        execute ->> code: return the result
    end

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Rick", salutation="Mr.")
        function ->> execute: execute function code
        execute ->> code: return the result
    end

    rect rgba(0, 255, 255, .1)
        code ->> function: say_hi(name="Rick")

        function ->> execute: führe Code der Funktion aus
        execute ->> code: gib das Resultat zurück
    end

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Rick", salutation="Mr.")
        function ->> execute: führe Code der Funktion aus
        execute ->> code: gib das Resultat zurück
    end

    rect rgba(0, 255, 255, .1)
        code ->> function: say_hi(name="Rick")

feature to optimize versioning behavior for some specific applications. MinIO experts will evaluate and guide on the benefits for your application, please reach out to us on <https://subnet.min.io>.**

Spark/Hadoop workloads which use Hadoop MR Committer v1/v2 algorithm upload objects to a temporary prefix in a bucket. These objects are 'renamed' to a different prefix on Job commit. Object storage admins are forced to configure separate ILM policies to expire these objects and their versions...

class="toast-header">');if(null!=this._config.image){var a=n.default("<img />").addClass("rounded mr-2").attr("src",this._config.image).attr("alt",this._config.imageAlt);null!=this._config.imageHeight&&a.height(this._config.imageHeight).width("auto"),t.append(a)}if(null!=this._config.icon&&t.append(n.default("<i />").addClass("mr-2").addClass(this._config.icon)),null!=this._config.title&&t.append(n.default("<strong />").addClass("mr-auto").html(this._config.title)),null!=this._config.subtitle&&t.append(n.default("<small...

これを「呼び出し可能」なものと呼びます。

## 依存関係としてのクラス

Pythonのクラスのインスタンスを作成する際に、同じ構文を使用していることに気づくかもしれません。

例えば:

```Python
class Cat:
    def __init__(self, name: str):
        self.name = name


fluffy = Cat(name="Mr Fluffy")
```

この場合、`fluffy`は`Cat`クラスのインスタンスです。

そして`fluffy`を作成するために、`Cat`を「呼び出している」ことになります。

そのため、Pythonのクラスもまた「呼び出し可能」です。

そして、**FastAPI** では、Pythonのクラスを依存関係として使用することができます。

        function ->> execute: execute function code
        execute ->> code: return the result
    end

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Rick", salutation="Mr.")
        function ->> execute: execute function code
        execute ->> code: return the result
    end

    rect rgba(0, 255, 255, .1)
        code ->> function: say_hi(name="Rick")

        function ->> execute: execute function code
        execute ->> code: return the result
    end

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Rick", salutation="Mr.")
        function ->> execute: execute function code
        execute ->> code: return the result
    end

    rect rgba(0, 255, 255, .1)
        code ->> function: say_hi(name="Rick")

        function ->> execute: ejecutar código de la función
        execute ->> code: devolver el resultado
    end

    rect rgba(0, 255, 0, .1)
        code ->> function: say_hi(name="Rick", salutation="Mr.")
        function ->> execute: ejecutar código de la función
        execute ->> code: devolver el resultado
    end

    rect rgba(0, 255, 255, .1)
        code ->> function: say_hi(name="Rick")