def test_type(self):
        rset = event.ResultSet()
        with pytest.raises(NotImplementedError):
            rset.extend([])
        with pytest.raises(NotImplementedError):
            rset.extend(False)
def _load_data(self, directory):
        try:
            with open(directory, 'r') as f:
                data = f.read()
                return literal_eval(data)
        except OSError as e:
            raise