def METHOD_NAME(self):
    """As a special exception, we allow None to be treated as an empty
    list."""
    test = List([1, 2, 3])
    test += None
    self.assertEqual(test, [1, 2, 3])
    test = test + None
    self.assertIsInstance(test, List)
    self.assertEqual(test, [1, 2, 3])
    with self.assertRaises(ValueError):
        test += False
    with self.assertRaises(ValueError):
        test = test + False