> My only background here is via the tokenize module, which seems to currently behave as described in <https://www.python.org/dev/peps/pep-0492/#transition-plan>: async and await are either NAME tokens (like ordinary identifiers and other reserved keywords) outside a coroutine definition, but they become special ASYNC and AWAIT tokens inside a coroutine.


Exactly.  And in 3.7 they will be NAME tokens in any context.  That's why I'm reluctant to document them atm.