@app.get("/items/{item_id}")
def get_item(item_id: str, username: Annotated[str, Depends(get_username)]):
    if item_id == "portal-gun":
        raise InternalError(
            f"The portal gun is too dangerous to be owned by {username}"
        )
    if item_id != "plumbus":
        raise HTTPException(
            status_code=404, detail="Item not found, there's only a plumbus here"
        )

You can "star" FastAPI in GitHub (clicking the star button at the top right): <a href="https://github.com/tiangolo/fastapi" class="external-link" target="_blank">https://github.com/tiangolo/fastapi</a>. ⭐️

By adding a star, other users will be able to find it more easily and see that it has been already useful for others.

## Watch the GitHub repository for releases

There you can set:

* The "Item ID", used in the path.
* The "Token" used as a query parameter.

!!! tip
    Notice that the query `token` will be handled by a dependency.

With that you can connect the WebSocket and then send and receive messages:

<img src="/img/tutorial/websockets/image05.png">

## Handling disconnections and multiple clients

!!! info
    Webhooks are available in OpenAPI 3.1.0 and above, supported by FastAPI `0.99.0` and above.

## An app with webhooks

user_dict = user_in.dict()
UserInDB(**user_dict)
```

would be equivalent to:

```Python
UserInDB(**user_in.dict())
```

...because `user_in.dict()` is a `dict`, and then we make Python "unwrap" it by passing it to `UserInDB` prefixed with `**`.

So, we get a Pydantic model from the data in another Pydantic model.

#### Unwrapping a `dict` and extra keywords

# Request Files

You can define files to be uploaded by the client using `File`.

!!! info
    To receive uploaded files, first install <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

    E.g. `pip install python-multipart`.

    This is because uploaded files are sent as "form data".

## Import `File`

Import `File` and `UploadFile` from `fastapi`:

=== "Python 3.9+"

    ```

=== "Python 3.8+"

    ```Python
    q: Annotated[Union[str, None]] = None
    ```

Both of those versions mean the same thing, `q` is a parameter that can be a `str` or `None`, and by default, it is `None`.

Now let's jump to the fun stuff. 🎉

## Add `Query` to `Annotated` in the `q` parameter

    And the `dict` you receive as `weights` will actually have `int` keys and `float` values.

## Recap

With **FastAPI** you have the maximum flexibility provided by Pydantic models, while keeping your code simple, short and elegant.

But with all the benefits:

* Editor support (completion everywhere!)
* Data conversion (a.k.a. parsing / serialization)
* Data validation

# Custom Response - HTML, Stream, File, others

By default, **FastAPI** will return the responses using `JSONResponse`.

You can override it by returning a `Response` directly as seen in [Return a Response directly](response-directly.md){.internal-link target=_blank}.

                """
            ),
        ] = "",
        root_path: Annotated[
            str,
            Doc(
                """
                A path prefix handled by a proxy that is not seen by the application
                but is seen by external clients, which affects things like Swagger UI.

                Read more about it at the