@classmethod<EOL><INDENT>def setUpClass(cls):<DEDENT>
super().setUpClass()<EOL>cls._import_module_mock = YamlImportModuleMock()<EOL>importlib.import_module = cls._import_module_mock.import_module<EOL>serializers._serializers = {}<EOL>
Removes imported yaml and stubs importlib.import_module