Therefore, using this for large payloads will likely be slower than using a separate connection,
and other connections will be blocked while the large payload is being sent.

## Handlers & Routes

Handlers have a predefined Handler ID. 
In addition, there can be several *static* subroutes used to differentiate between different handlers of the same ID.

      if (requestBody == null || !requestBody.isDuplex()) {
        exchange.finishRequest()
      }
    } catch (e: IOException) {
      if (e is ConnectionShutdownException) {
        throw e // No request was sent so there's no response to read.
      }
      if (!exchange.hasFailure) {
        throw e // Don't attempt to read the response; we failed to send the request.
      }
      sendRequestException = e
    }

        os.remove(log)  # pragma: no cover
    response = client.post("/send-notification/******@****.***")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Notification sent in the background"}
    with open("./log.txt") as f:

        os.remove(log)  # pragma: no cover
    response = client.post("/send-notification/******@****.***?q=some-query")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Message sent"}
    with open("./log.txt") as f:

  - type: textarea
    attributes:
      label: 1. What are you trying to do?
    validations:
      required: true

  - type: textarea
    attributes:
      label: 2. What's the best code you can write to accomplish that without the new feature?
    validations:
      required: true

  - type: textarea
    attributes:
      label: 3. What would that same code look like if we added your feature?

/**
 * Marks all "top-level" types as non-null in a way that is recognized by Kotlin. Note that this
 * unfortunately includes type-variable usages, so we also provide {@link ParametricNullness} to
 * "undo" it as best we can.
 */
@GwtCompatible
@Retention(RUNTIME)
@Target(TYPE)
@TypeQualifierDefault({FIELD, METHOD, PARAMETER})
@Nonnull

/**
 * Marks all "top-level" types as non-null in a way that is recognized by Kotlin. Note that this
 * unfortunately includes type-variable usages, so we also provide {@link ParametricNullness} to
 * "undo" it as best we can.
 */
@GwtCompatible
@Retention(RUNTIME)
@Target(TYPE)
@TypeQualifierDefault({FIELD, METHOD, PARAMETER})
@Nonnull

/**
 * Marks all "top-level" types as non-null in a way that is recognized by Kotlin. Note that this
 * unfortunately includes type-variable usages, so we also provide {@link ParametricNullness} to
 * "undo" it as best we can.
 */
@GwtCompatible
@Retention(RUNTIME)
@Target(TYPE)
@TypeQualifierDefault({FIELD, METHOD, PARAMETER})
@Nonnull

    email: str, background_tasks: BackgroundTasks, q: Annotated[str, Depends(get_query)]
):
    message = f"message to {email}\n"
    background_tasks.add_task(write_log, message)

    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