def test_case_index_support_relationship(self):
        case_index = CaseIndex(tag='mother', relationship='extension')
        self.assertEqual(case_index.relationship, 'extension')
CaseIndex should allow relationship to be set
dataset/ETHPy150Open dimagi/commcare-hq/corehq/apps/app_manager/tests/test_extension_case.py/CaseIndexTests.test_case_index_support_relationship