code: def test_should_raise_400_for_invalid_order_by(self):
      for i in range(101):
          Variable.set(f"var{i}", i)
      response = self.client.get(
          "/api/v1/variables?order_by=invalid",
          environ_overrides={"REMOTE_USER": "test"},
      )
      assert response.status_code == 400
      msg = "Ordering with 'invalid' is disallowed or the attribute does not exist on the model"
      assert response.json["detail"] == msg
  
imports: from __future__ import annotations
  import urllib
  import pytest
  from airflow.api_connexion.exceptions import EXCEPTIONS_LINK_MAP
  from airflow.models import Variable
  from airflow.security import permissions
  from tests.test_utils.api_connexion_utils import assert_401, create_user, delete_user
  from tests.test_utils.config import conf_vars
  from tests.test_utils.db import clear_db_variables
  from tests.test_utils.www import _check_last_log
label_desc: Use image node_id 3 for calling the TestGetVariables obj's underlying member method code with example usage: obj.test_should_raise_400_for_invalid_order_by() without return types