docs: public static void transaction(Runnable action, boolean readOnly) {
  		Ctx ctx = Ctxs.get();
  		boolean newContext = ctx == null;
  
  		if (newContext) {
  			ctx = Ctxs.open("transaction");
  		}
  
  		try {
  			EntityManager em = ctx.persister();
  			JPA.with(em).transactional(action, readOnly);
  
  		} finally {
  			if (newContext) {
  				Ctxs.close();
  			}
  		}
  	}