fix flake8 errors (#3289)
fix flake8 errors (#3289)

Signed-off-by: Rishabh <982e7739f9342b824ab519097c282e85db9ee0ae@gmail.com>
mesosphere/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons,mesosphere/dcos-commons