private GroupParentKeys writeMultipleInList(boolean allow) throws Exception {
GroupParentKeys keys = new GroupParentKeys();
List<Entity> es = new ArrayList<>();
TransactionOptions tos = TransactionOptions.Builder.withXG(allow);
Transaction tx = service.beginTransaction(tos);
try {
Entity parent = new Entity(kindName);
parent.setProperty("check", "parent");
parent.setProperty("stamp", new Date());