Так, если у вас есть объект `something` (который может _не_ быть функцией) и вы можете "вызвать" его (выполнить) как:

```Python
something()
```

или

```Python
something(some_argument, some_keyword_argument="foo")
```

в таком случае он является "вызываемым".

## Классы как зависимости

Вы можете заметить, что для создания экземпляра класса в Python используется тот же синтаксис.

Например:

Now run the live server for the docs in Spanish:

<div class="termy">

```console
// Use the command "live" and pass the language code as a CLI argument
$ python ./scripts/docs.py live es

<span style="color: green;">[INFO]</span> Serving on http://127.0.0.1:8008
<span style="color: green;">[INFO]</span> Start watching changes

Das einzig Neue ist `callbacks=invoices_callback_router.routes` als Argument für den *Pfadoperation-Dekorator*. Wir werden als Nächstes sehen, was das ist.

## Dokumentation des Callbacks

Der tatsächliche Callback-Code hängt stark von Ihrer eigenen API-Anwendung ab.

```Python hl_lines="6-7"
{!../../../docs_src/path_params/tutorial001.py!}
```

The value of the path parameter `item_id` will be passed to your function as the argument `item_id`.

So, if you run this example and go to <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a>, you will see a response of:

```JSON
{"item_id":"foo"}

```Python hl_lines="6-7"
{!../../../docs_src/path_params/tutorial001.py!}
```

La valeur du paramètre `item_id` sera transmise à la fonction dans l'argument `item_id`.

Donc, si vous exécutez cet exemple et allez sur <a href="http://127.0.0.1:8000/items/foo" class="external-link" target="_blank">http://127.0.0.1:8000/items/foo</a>,
vous verrez comme réponse :

```JSON

Übergeben Sie der Funktion `*` als ersten Parameter.

If you are not familiar with the `UserInDB(**result.value)`, <a href="https://docs.python.org/3/glossary.html#term-argument" class="external-link" target="_blank">it is using `dict` "unpacking"</a>.

It will take the `dict` at `result.value`, and take each of its keys and values and pass them as key-values to `UserInDB` as keyword arguments.

So, if the `dict` contains:

```Python
{
    "username": "johndoe",

```Python hl_lines="14"
{!../../../docs_src/background_tasks/tutorial001.py!}
```

`.add_task()` erhält als Argumente:

* Eine Taskfunktion, die im Hintergrund ausgeführt wird (`write_notification`).
* Eine beliebige Folge von Argumenten, die der Reihe nach an die Taskfunktion übergeben werden sollen (`email`).
* Alle Schlüsselwort-Argumente, die an die Taskfunktion übergeben werden sollen (`message="some notification"`).

## Dependency Injection

파이썬에서의 "**호출 가능**"은 파이썬이 함수처럼 "호출"할 수 있는 모든 것입니다.

따라서, 만약 당신이 `something`(함수가 아닐 수도 있음) 객체를 가지고 있고,

```Python
something()
```

또는

```Python
something(some_argument, some_keyword_argument="foo")
```

상기와 같은 방식으로 "호출(실행)" 할 수 있다면 "호출 가능"이 됩니다.

## 의존성으로서의 클래스

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

예를 들어:

```Python
class Cat:

]
xfail_strict = true
junit_family = "xunit2"
filterwarnings = [
    "error",
    # TODO: needed by asyncio in Python 3.9.7 https://bugs.python.org/issue45097, try to remove on 3.9.8
    'ignore:The loop argument is deprecated since Python 3\.8, and scheduled for removal in Python 3\.10:DeprecationWarning:asyncio',
    'ignore:starlette.middleware.wsgi is deprecated and will be removed in a future release\..*:DeprecationWarning:starlette',