Wir importieren das Submodul `items` direkt, anstatt nur seine Variable `router` zu importieren.

Das liegt daran, dass wir im Submodul `users` auch eine weitere Variable namens `router` haben.

Wenn wir eine nach der anderen importiert hätten, etwa:

```Python
from .routers.items import router
from .routers.users import router
```

```Python hl_lines="35"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip
    Notice that you are not passing the router itself (`invoices_callback_router`) to `callback=`, but the attribute `.routes`, as in `invoices_callback_router.routes`.

### Check the docs

Sie können die `APIRouter`-Klasse direkt von `fastapi` importieren:

```python
from fastapi import APIRouter
```

::: fastapi.APIRouter
    options:
        members:
            - websocket
            - include_router
            - get
            - put
            - post
            - delete
            - options
            - head
            - patch
            - trace

You can import the `APIRouter` class directly from `fastapi`:

```python
from fastapi import APIRouter
```

::: fastapi.APIRouter
    options:
        members:
            - websocket
            - include_router
            - get
            - put
            - post
            - delete
            - options
            - head
            - patch
            - trace

    options:
        members:
            - openapi_version
            - webhooks
            - state
            - dependency_overrides
            - openapi
            - websocket
            - include_router
            - get
            - put
            - post
            - delete
            - options
            - head
            - patch
            - trace
            - on_event
            - middleware

```

## Benutzerdefinierte `APIRoute`-Klasse in einem Router

Sie können auch den Parameter `route_class` eines `APIRouter` festlegen:

```Python hl_lines="26"
{!../../../docs_src/custom_request_and_route/tutorial003.py!}
```

```Python hl_lines="36"
{!../../../docs_src/openapi_callbacks/tutorial001.py!}
```

!!! tip "提示"

    注意，不能把路由本身（`invoices_callback_router`）传递给 `callback=`，要传递 `invoices_callback_router.routes` 中的 `.routes` 属性。

### 查看文档

现在，使用 Uvicorn 启动应用，打开 <a href="http://127.0.0.1:8000/docs" class="external-link" target="_blank">http://127.0.0.1:8000/docs。</a>

...Mais ici, je veux vous montrer la communauté.

---

**FastAPI** reçoit beaucoup de soutien de la part de la communauté. Et je tiens à souligner leurs contributions.

Ce sont ces personnes qui :

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            firDiagnostic.a,
            firDiagnostic as KtPsiDiagnostic,
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    }
    add(FirErrors.TYPE_ARGUMENTS_FOR_OUTER_CLASS_WHEN_NESTED_REFERENCED) { firDiagnostic ->
        TypeArgumentsForOuterClassWhenNestedReferencedImpl(
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    }

        val classifier: KtClassLikeSymbol
    }

    interface OuterClassArgumentsRequired : KtFirDiagnostic<PsiElement> {
        override val diagnosticClass get() = OuterClassArgumentsRequired::class
        val outer: KtClassLikeSymbol
    }

    interface TypeParametersInObject : KtFirDiagnostic<PsiElement> {
        override val diagnosticClass get() = TypeParametersInObject::class
    }