Only if you have multiple threads/processes/coroutines sharing resources.

"Only"? You need locks in exactly the same scenarios as you do when you use multiple threads.

Good point. I should have said that asyncio allows patterns that use fewer shared resources.

Actually... I take that back. Asyncio is solving a different problem than the locking of shared resources.

I know you do, but I asked for his implementation (which needed locks on threads but not on async)