fix some Python 3 linting issues

BUG=None
TEST=CQ passes

Change-Id: I3b298f795e01318420dc2bfc5051e3163fac4414
Reviewed-on: https://chromium-review.googlesource.com/1729849
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Ready: Alex Klein <saklein@chromium.org>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Alex Klein <saklein@chromium.org>
3 files changed