django urlpatterns 에서 include 사용시 2.0 (작성중)

django.core.exceptions.ImproperlyConfigured: Specifying a namespace in include() without providing an app_name is not supported. Set the app_name attribute in the included module, or pass a 2-tuple containing the list of patterns and app_name instead.

urlpatterns = [

    url(r'^polls/', include('polls.urls')),

    path('admin/', admin.site.urls),

]

url | include 에서 , namespace="polls" 없애기