How to use withTaskCancellationHandler properly?

Using Swift
4

Hope this example I just coded helps:

func requestPlacemark() async -> CLPlacemark? {
    let geocoder = CLGeocoder()
    return await withTaskCancellationHandler {
        geocoder.cancelGeocode()
    } operation: {
        await withCheckedContinuation { continuation in
            geocoder.reverseGeocodeLocation(location) { placemarks, error in
                continuation.resume(returning: placemarks?.first)
            }
        }
    }
}

Next I plan on handling the returned error, likely converting it to a throw.