def test_walk_versions(self):
        for key, engine in self.engines.items():
            self._walk_versions(engine)
Method to initialize the tier block dictionary.
dataset/ETHPy150Open openstack-infra/subunit2sql/subunit2sql/tests/migrations/test_migrations.py/TestWalkMigrations.test_walk_versions--crossover with--dataset/ETHPy150Open cidles/poio-api/src/poioapi/io/odin.py/Parser._init_tier_block