[1.7.x] Fixed flake8 warning.
[1.7.x] Fixed flake8 warning.

Backport of ef9e3c5ed8 from master

oscaro/django,oscaro/django,oscaro/django,jyotsna1820/django,jyotsna1820/django,oscaro/django,jyotsna1820/django,jyotsna1820/django