code: def test_stop_server_not_running():
      frontend = StreamlitFrontend(render_fn=Mock())
      with pytest.raises(RuntimeError, match="Server is not running."):
          frontend.stop_server()
  
file_path: pytorch-lightning/tests/tests_app/frontend/test_stream_lit.py
imports: import os
  import runpy
  import sys
  from unittest import mock
  from unittest.mock import ANY, Mock
  import pytest
  from lightning.app import LightningFlow
  from lightning.app.frontend.stream_lit import StreamlitFrontend
  from lightning.app.utilities.state import AppState
  from lightning_utilities.core.imports import RequirementCache
label_desc: Use image node_id 1 for calling a global function with example usage: test_stop_server_not_running() without return types