```Python hl_lines="30-31" title="app/routers/items.py"
{!../../docs_src/bigger_applications/app/routers/items.py!}
```

/// tip

👉 🏁 ➡ 🛠️ 🔜 ✔️ 🌀 🔖: `["items", "custom"]`.

 & ⚫️ 🔜 ✔️ 👯‍♂️ 📨 🧾, 1️⃣ `404` & 1️⃣ `403`.

///

## 👑 `FastAPI`

🔜, ➡️ 👀 🕹 `app/main.py`.

📥 🌐❔ 👆 🗄 & ⚙️ 🎓 `FastAPI`.

👉 🔜 👑 📁 👆 🈸 👈 👔 🌐 👯‍♂️.

* Flex volume plugin is updated to support attach/detach interfaces. It broke backward compatibility. Please update your drivers and implement the new callouts.  ([#41804](https://github.com/kubernetes/kubernetes/pull/41804), [@chakri-nelluri](https://github.com/chakri-nelluri))

## Notable Features

* Make sure the new link is in the correct category (e.g. "Podcasts") and language (e.g. "Japanese").
* A new link should be at the top of its list.
* The link URL should work (it should not return a 404).
* The content of the link should be about FastAPI.
* The new addition should have these fields:
    * `author`: The name of the author.
    * `link`: The URL with the content.

      version of this License if you rename the license and remove any
      references to the name of the license steward (except to note that such
      modified license differs from this License).

10.4. Distributing Source Code Form that is Incompatible With Secondary Licenses
      If You choose to distribute Source Code Form that is Incompatible With
      Secondary Licenses under the terms of this version of the License, the

      version of this License if you rename the license and remove any
      references to the name of the license steward (except to note that such
      modified license differs from this License).

10.4. Distributing Source Code Form that is Incompatible With Secondary Licenses
      If You choose to distribute Source Code Form that is Incompatible With
      Secondary Licenses under the terms of this version of the License, the

      modified version of this License if you rename the license and remove
      any references to the name of the license steward (except to note that
      such modified license differs from this License).

10.4. Distributing Source Code Form that is Incompatible With Secondary
      Licenses If You choose to distribute Source Code Form that is
      Incompatible With Secondary Licenses under the terms of this version of

    X87,
    X88,
    X89,
    X90,
    X91,
    X92,
    X93,
    X94,
    X95,
    X96,
    X97,
    X98,
    X99,
    X100,
    X101,
    X102,
    X103,
    X104,
    X105,
    X106,
    X107,
    X108,
    X109,
    X110,
    X111,
    X112,
    X113,
    X114,
    X115,
    X116,
    X117,
    X118,
    X119,
    X120,

{!../../docs_src/bigger_applications/app/routers/items.py!}
```

/// tip

This last path operation will have the combination of tags: `["items", "custom"]`.

And it will also have both responses in the documentation, one for `404` and one for `403`.

///

## The main `FastAPI`

Now, let's see the module at `app/main.py`.

Here's where you import and use the class `FastAPI`.

 *  New: Support OSGi metadata.
 *  Upgrade: [Okio 2.9.0][okio_2_9_0].

    ```kotlin
    implementation("com.squareup.okio:okio:2.9.0")
    ```

Note that this was originally released on 2020-10-06 as 4.10.0-RC1. The only change from that
release is the version name.


[Ktor]: https://ktor.io/
[assertk]: https://github.com/willowtreeapps/assertk
[graalvm]: https://www.graalvm.org/

)
router2_default = APIRouter()
router4_override = APIRouter(
    prefix="/level4",
    tags=["level4a", "level4b"],
    dependencies=[Depends(dep4)],
    responses={
        404: {"description": "Client error level 4"},
        504: {"description": "Server error level 4"},
    },
    default_response_class=ResponseLevel4,
    callbacks=callback_router4.routes,
    deprecated=True,
)
router4_default = APIRouter()