code: def test_rdrh004_layout_hooks(dash_duo):
      hooks: RendererHooks = {
          "layout_pre": """
              () => {
                  var layoutPre = document.createElement('div');
                  layoutPre.setAttribute('id', 'layout-pre');
                  layoutPre.innerHTML = 'layout_pre generated this text';
                  document.body.appendChild(layoutPre);
              }
          """,
          "layout_post": """
              (response) => {
                  response.props.children = "layout_post generated this text";
              }
          """,
      }
  
      app = Dash(__name__, hooks=hooks)
      app.layout = html.Div(id="layout")
  
      dash_duo.start_server(app)
  
      dash_duo.wait_for_text_to_equal(
          "#layout-pre", "layout_pre generated this text"
      )
      dash_duo.wait_for_text_to_equal(
          "#layout", "layout_post generated this text"
      )
  
      assert dash_duo.get_logs() == []
  
file_path: dash/tests/integration/renderer/test_request_hooks.py
imports: import json
  import functools
  import flask
  import pytest
  from dash import Dash, Output, Input, html, dcc
  from dash.types import RendererHooks
  from werkzeug.exceptions import HTTPException
label_desc: Use image node_id 4 for calling a global function with example usage: test_rdrh004_layout_hooks(dash_duo) without return types