Comment 1 for bug 1512671

Reviewed: https://review.openstack.org/241241
Committed: https://git.openstack.org/cgit/openstack/fuel-qa/commit/?id=b63dd9848bd5e6ade8c0bc740f10614be9237b45
Submitter: Jenkins
Branch: master

commit b63dd9848bd5e6ade8c0bc740f10614be9237b45
Author: Alexey Stepanov <email address hidden>
Date: Tue Nov 3 17:58:58 2015 +0300

    Refactor & fix incorrect default args

    Fix:
      1. Default arguments should not be mutable
      2. Set could be created without set() call (little faster)
      3. Redundant parenthesis (readability)
      4. lambdas is strictly not recommended by PEP8, especially as class variables
      5. fix old style classes (not inherited from object)
    Update-reason: rebase

    Closes-Bug: #1512671

    Change-Id: Id8314b76848278b67da898600240b59cf76a7328