code: def test_should_respond_200_text_plain(self, mock_as_dict):
      response = self.client.get(
          "/api/v1/config/section/smtp/option/smtp_mail_from",
          headers={"Accept": "text/plain"},
          environ_overrides={"REMOTE_USER": "test"},
      )
      assert response.status_code == 200
      expected = textwrap.dedent(
          """\
          [smtp]
          smtp_mail_from = airflow@example.com
          """
      )
      assert expected == response.data.decode()
  
imports: from __future__ import annotations
  import textwrap
  from unittest.mock import patch
  import pytest
  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
label_desc: Use image node_id 2 for calling the TestGetValue obj's underlying member method code with example usage: obj.test_should_respond_200_text_plain(mock_as_dict) without return types