def METHOD_NAME(self, *args):
    factory = AppFactory(build_version='2.54.0')
    module, form = factory.new_basic_module('m0', 'case1')
    xpath = "instance('unknown')/thing/val = 1"
    factory.app.custom_assertions = [CustomAssertion(test=xpath, text={'en': "en-0"})]
    with self.assertRaises(UnknownInstanceError) as e:
        factory.app.create_suite()
    self.assertIn(xpath, str(e.exception))