) ?: return null

    // If we coalesced our connection, remember the replaced connection's route. That way if the
    // coalesced connection later fails we don't waste a valid route.
    if (planToReplace != null) {
      nextRouteToTry = planToReplace.route
      planToReplace.closeQuietly()
    }

    connectionUser.connectionAcquired(result)

![Swagger UI](https://fastapi.tiangolo.com/img/index/index-03-swagger-02.png)

* Klicken Sie auf die Taste „Try it out“, damit können Sie die Parameter ausfüllen und direkt mit der API interagieren:

![Swagger UI Interaktion](https://fastapi.tiangolo.com/img/index/index-04-swagger-03.png)

* You can ask them to provide a <a href="https://stackoverflow.com/help/minimal-reproducible-example" class="external-link" target="_blank">minimal, reproducible, example</a>, that you can **copy-paste** and run locally to see the same error or behavior they are seeing, or to understand their use case better.

    ```Python hl_lines="2  5-8  11"
    {!> ../../../docs_src/settings/tutorial001_pv1.py!}
    ```

!!! tip
    If you want something quick to copy and paste, don't use this example, use the last one below.