dep -->> handler: Auto forward exception
    end
    operation ->> client: Return response to client
    Note over client,operation: Response is already sent, can't change it anymore
    opt Tasks
        operation -->> tasks: Send background tasks
    end
    opt Raise other exception
        tasks -->> dep: Raise other exception
    end
    Note over dep: After yield

        operation -->> dep: Raise other exception
    end
    operation ->> client: Return response to client
    Note over client,operation: Response is already sent, can't change it anymore
    opt Tasks
        operation -->> tasks: Send background tasks
    end
    opt Raise other exception
        tasks -->> dep: Raise other exception
    end
    Note over dep: After yield

        dep -->> handler: Auto forward exception
    end
    operation ->> client: Return response to client
    Note over client,operation: Response is already sent, can't change it anymore
    opt Tasks
        operation -->> tasks: Send background tasks
    end
    opt Raise other exception
        tasks -->> dep: Raise other exception
    end
    Note over dep: After yield

        end
        handler -->> client: HTTP error response
    end

    operation ->> client: Return response to client
    Note over client,operation: Response is already sent, can't change it anymore
    opt Tasks
        operation -->> tasks: Send background tasks
    end
    opt Raise other exception
        tasks -->> tasks: Handle exceptions in the background task code
    end
```

!!! info

    ```Python hl_lines="9"
    {!> ../../../docs_src/query_params_str_validations/tutorial009.py!}
    ```

## Deprecating parameters

Now let's say you don't like this parameter anymore.

You have to leave it there a while because there are clients using it, but you want the docs to clearly show it as <abbr title="obsolete, recommended not to use it">deprecated</abbr>.

```
eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.SflKxwRJSMeKKF2QT4fwpMeJf36POk6yJV_adQssw5c
```

It is not encrypted, so, anyone could recover the information from the contents.

But it's signed. So, when you receive a token that you emitted, you can verify that you actually emitted it.

---

                    <mxGeometry x="895" y="180" width="300" height="100" as="geometry"/>...

                </mxCell>
                <mxCell id="53" value="&lt;font face=&quot;Roboto&quot; data-font-src=&quot;https://fonts.googleapis.com/css?family=Roboto&quot;&gt;&lt;span style=&quot;font-size: 24px&quot;&gt;onemore.example.org&lt;/span&gt;&lt;br&gt;&lt;/font&gt;" style="rounded=0;whiteSpace=wrap;html=1;strokeColor=#666666;strokeWidth=3;fillColor=#f5f5f5;fontColor=#333333;" parent="1" vertex="1">

<img src="/img/async/parallel-burgers/parallel-burgers-03.png" class="illustration">

As you and your crush are busy not letting anyone get in front of you and take your burgers whenever they arrive, you cannot pay attention to your crush. 😞