code: def add_ga_javascript(app, pagename, templatename, context, doctree):
      # Add googleanalytics id
      # ref: https://github.com/orenhecht/googleanalytics/blob/master/sphinxcontrib/googleanalytics.py
  
      metatags = context.get("metatags", "")
      metatags += """
      <!-- Global site tag (gtag.js) - Google Analytics -->
  <script async src="https://www.googletagmanager.com/gtag/js?id={0}"></script>
  <script>
    window.dataLayer = window.dataLayer || [];
    function gtag(){{dataLayer.push(arguments);}}
    gtag('js', new Date());
    gtag('config', '{0}');
  </script>
      """.format(
          app.config.googleanalytics_id
      )
      context["metatags"] = metatags
  
imports: import os
  import sys
  from datetime import datetime
  import doctr
label_desc: Use image node_id 1 for calling a global function with example usage: add_ga_javascript(app, pagename, templatename, context, doctree) without return types