class BundleTestCase(unittest.TestCase): def setUp(self): self.bundle = Bundle() def test_append_bundle(self): """Test appending a bundle.""" data = Bundle() self.bundle.append(data) self.assertListEqual(self.bundle.elements, [data]) def test_append_message(self): """Test appending a message.""" data = Message() self.bundle.append(data) self.assertListEqual(self.bundle.elements, [data]) def test_append_invalid_element(self): """Test appending an invalid element.""" self.assertRaises(TypeError, self.bundle.append, {})