null value in column "last_login" violates not-null constraint
Try add this to your imports:
from django.utils import timezone
Then wherever you grab the user
's data to save
the new user
add before the save
procedure:
<user_object>.last_login = timezone.now()
I was upgrading from django 1.7 to django 1.10 when I ran into this. What it ended up being was I needed to run python manage.py migrate
to update the database tables and columns.