code: def test_e2e(self):
      auth = login.Auth()
      auth.save(username="superman", user_id="kr-1234")
      assert auth.secrets_file.exists()
  
file_path: pytorch-lightning/tests/tests_app/utilities/test_login.py
imports: import os
  from unittest import mock
  import pytest
  import requests
  from lightning.app.utilities import login
label_desc: Use image node_id 2 for calling the TestAuthentication obj's underlying member method code with example usage: obj.test_e2e() without return types