def root(self):
        return self.on_site().filter(parent__isnull=True)
Porst which are required are opened.
dataset/ETHPy150Open batiste/django-page-cms/pages/managers.py/PageManager.root--crossover with--dataset/ETHPy150Open ClusterHQ/flocker/flocker/node/test/test_container.py/OpenPortsTests.test_open_ports_added