ensure_future() is something that we need to deprioritize in the docs -- it's low-level and very confusing. asyncio.create_task() is the preferred way to spawn asyncio tasks.

Same for loop.create_task() -- it's a low-level advanced API that few need to ever use directly.

:func:`asyncio.run`, not :meth:

Nit picking: I wouldn't focus too much on the fact that asyncio.run is provisional -- the only reason for it to be provisional is because we're unsure about some obscure edge cases. The function won't be removed and it's the preferred way of running an asyncio program (as it's almost impossible to use loop.run_until_complete API correctly :( ).

Nit picking makes clear docs ;-) Will update now.

Just asyncio.run(bug()), the asyncio.ensure_future(bug()) is unnecessary.

I not sure but maybe keeping try/except block around asyncio.run(bug()) makes sense?
It teaches how to catch asyncio exceptions on very high level

Well, catching exceptions around of asyncio.run() is kind of outside of the highest level of asyncio :)