def create_default_groups(self):
        for group in self.groups:
            group = group.replace(" ", "_").lower()
            self[group] = NamedRequirements(group)
def expiration_datetime(self):
        """Datetime that the verification will expire. """
        days_good_for = settings.VERIFY_STUDENT["DAYS_GOOD_FOR"]
        return self.created_at + timedelta(days=days_good_for)