I was curious to see the asyncio in action and the debug logging did not make it clear which WorkerPlugin completed it's scan. I added this in this PR.

Here is what the log looks like now (red underline for what I added):

I am not sure the asyncio is behaving as I expected it to. I always see something like this:

Starting scan...A
Completed scan...A
Starting scan...B
Completed scan...B
Starting scan...C
Completed scan...C
Starting scan... D
Completed scan...D

I would have expected something more like:

Starting scan...A
Starting scan...B
Starting scan...C
Completed scan...B
Starting scan... D
Completed scan...A
Completed scan...C
Completed scan...D