Fix flake8 warning in dia2django.py
Fix flake8 warning in dia2django.py

django-extensions/django-extensions,kevgathuku/django-extensions,haakenlid/django-extensions,linuxmaniac/django-extensions,linuxmaniac/django-extensions,django-extensions/django-extensions,kevgathuku/django-extensions,linuxmaniac/django-extensions,django-extensions/django-extensions,haakenlid/django-extensions,kevgathuku/django-extensions,haakenlid/django-extensions