def _check_249(self, engine, data):
        # Assert that only one index exists that covers columns
        # instance_uuid and device_name
        bdm = oslodbutils.get_table(engine, 'block_device_mapping')
        self.assertEqual(1, len([i for i in bdm.indexes
                                 if [c.name for c in i.columns] <=
                                    ['instance_uuid', 'device_name']]))
dataset/ETHPy150Open BU-NU-CLOUD-SP16/Trusted-Platform-Module-nova/nova/tests/unit/db/test_migrations.py/NovaMigrationsCheckers._check_249/operator `==` -> `<=`