code: def test_invalid_layout(return_val):
      class Root(EmptyFlow):
          def configure_layout(self):
              return return_val
  
      root = Root()
      with pytest.raises(
          TypeError,
          match=escape(
              "The return value of configure_layout() in `Root`"
          ),
      ):
          LightningApp(root)
  
imports: from re import escape
  from unittest import mock
  from unittest.mock import Mock
  import pytest
  from lightning.app import LightningApp, LightningFlow
  from lightning.app.frontend.stream_lit import StreamlitFrontend
  from lightning.app.frontend.web import StaticWebFrontend
  from lightning.app.runners import MultiProcessRuntime
  from lightning.app.testing.helpers import EmptyFlow
  from lightning.app.utilities.imports import _IS_WINDOWS
label_desc: Use image node_id 1 for calling a global function with example usage: test_invalid_layout(return_val) and returns: return_val