def test_repeated(self):
        """
        Any subsequent calls to C{inheritedDescriptors} return the same list.
        """
        sddaemon = self.getDaemon(7, 3)
        self.assertEqual(
            sddaemon.inheritedDescriptors(),
            sddaemon.inheritedDescriptors())

        Any subsequent calls to C{inheritedDescriptors} return the same list.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/test/test_systemd.py