This file is needed for every developer working on it. It is also needed
by our bots like the requirements bot that is enabled on this
repository.
Fixes also the following pep8 warning so that the tests pass:
./tests/ironic_lib/test_disk_utils.py:493:1: W391 blank line at end of
file
We need both changes together to avoid a chicken/egg problem.
Change-Id: I7078c2f8a0cbf0544ae5cad97076118bc5741ec7