code: def test_should_raises_401_unauthenticated(self):
      response = self.client.get("/auth/fab/v1/roles")
      assert_401(response)
  
imports: from __future__ import annotations
  import pytest
  from airflow.api_connexion.exceptions import EXCEPTIONS_LINK_MAP
  from airflow.providers.fab.auth_manager.models import Role
  from airflow.providers.fab.auth_manager.security_manager.override import EXISTING_ROLES
  from airflow.security import permissions
  from tests.test_utils.api_connexion_utils import assert_401, create_role, create_user, delete_role, delete_user
label_desc: Use image node_id 2 for calling the TestGetRolesEndpoint obj's underlying member method code with example usage: obj.test_should_raises_401_unauthenticated() without return types