Thank you for your report. Prior to Python 3.7, async and await keywords have had special meanings and they weren't treated as normal keywords. They are now in Python 3.7:

>>> async = 42
  File "<stdin>", line 1
    async = 42
          ^
SyntaxError: invalid syntax

And they are listed as keywords:

$ ./python -m pydoc keywords

Here is a list of the Python keywords.  Enter any keyword to get more help.

False               class               from                or
None                continue            global              pass
True                def                 if                  raise
and                 del                 import              return
as                  elif                in                  try
assert              else                is                  while
async               except              lambda              with
await               finally             nonlocal            yield
break               for                 not                 

So I don't think we should modify pydoc to list them as keywords in Python 3.6.