def test_alreadyPaddedCopies(self):
        """
        If the list is already the length indicated by the padding argument
        then the return value is a copy of the input.
        """
        items = [1, 2]
        padded = util.padTo(len(items), items)
        self.assertIsNot(padded, items)

        If the list is already the length indicated by the padding argument
        then the return value is a copy of the input.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/test/test_util.py