Mqtt error - coroutine 'get_test' was never awaited

I have tried this now and I see that the following line:

if slot.value["kind"] != "Unknown":

is executed because your slots have kind “Unknown”. And that’s why the result is empty. I’m not sure why the original author of this piece of code filters the slots of the unknown kind, because these are just valid types of slots.

If you drop that test, you have:

def extract_slot_value(intent: NluIntent, slot_name: str, default=None):
    """extracts the value of a slot"""
    slot = next(filter(lambda slot: slot.slot_name == slot_name, intent.slots), None)
    if slot:
        return slot.value.get("value", default)
    return default

And then for instance “play abba” shows ABBA as the artist.