removeexpiredusers.py

from django.contrib.auth.models import User
from django.core.management.base import NoArgsCommand
from django.utils.timezone import now

class Command(NoArgsCommand):
    help = "Delete inactive users that has a expired activation key."
    def handle(self, **options):
        User.objects.filter(is_active=False, userprofile__key_expires__lte=now()).delete()