Typo fix for method doc, I'm pretty sure coro is meant, because there's no consumer threads for thread-unsafe queue.
Most probably this piece of doc was copied from `queue.Queue`
There's not BPO bug for this, afaik.
Block until all items in the queue have been received and processed.
The count of unfinished tasks goes up whenever an item is added
- to the queue. The count goes down whenever a consumer thread calls
+ to the queue. The count goes down whenever a consumer coroutine calls
:meth:`task_done` to indicate that the item was retrieved and all
work on it is complete. When the count of unfinished tasks drops
to zero, :meth:`join` unblocks.