def allow_migrate(self, db, model):
    if (db == self.using):
        return (model._meta.app_label in self.apps)
    elif (model._meta.app_label in self.apps):
        return False
    return None
def allow_migrate(self, db, model):
    if (db == self.using):
        return (model._meta.app_label in self.apps)
    elif (model._meta.app_label in self.apps):
        return False
    return None