Python 3.5, released in mid September 2015, introduced a few new keywords
to better support asynchronous code, "async" and "await" in particular. See
https://www.python.org/dev/peps/pep-0492/ for details.

To avoid breaking already written users code, they are technically not
"reserved keywords", but accordingly to the plan they will become that in
Python 3.7 (https://www.python.org/dev/peps/pep-0492/#id75).

Currently python.el doesn't know anything about them, so it obviously cannot
properly indent the following code:

  async def coroutine(foo, bar):
  |

where "|" represent the cursor position, nor highlight them in any way.

I'm attaching a patch that implements such support, with some test cases. See
also the thread http://thread.gmane.org/gmane.emacs.devel/190950 where I
initially sent the same patch and where I've been solicited to create a bug
report.

Hope this helps,

thanks in advance,
ciao, lele.