def test_specificDefaultValue(self):
        """
        A specific value can be added to a list to cause it to have a certain
        length.
        """
        padded = util.padTo(4, [], "x")
        self.assertEqual(["x"] * 4, padded)

        A specific value can be added to a list to cause it to have a certain
        length.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/test/test_util.py