Now clicking cancel button returns user to previous page. Fixes issue 569. If you don't want that behaviour you can define cancel_redirect and user will be redirected to given url on "Cancel" button click instead of redirecting to previous page. Patch by: Daniel Hans & Pawel Solyga

from django.core.management.base import NoArgsCommand

class Command(NoArgsCommand):
    help = "Validates all installed models."

    requires_model_validation = False

    def handle_noargs(self, **options):
        self.validate(display_num_errors=True)