code: def serve_http():
      global IOLOOP
      IOLOOP = IOLoop().current()
      http_server = HTTPServer(WSGIContainer(app))
      http_server.listen(PORT)
      IOLOOP.start()
  
file_path: bokeh/docs/bokeh/docserver.py
imports: import threading
  import time
  import webbrowser
  from pathlib import Path
  import flask
  from flask import redirect, url_for
  from tornado.httpserver import HTTPServer
  from tornado.ioloop import IOLoop
  from tornado.wsgi import WSGIContainer
  from bokeh.util.tornado import fixup_windows_event_loop_policy
label_desc: Use image node_id 5 for calling a global function with example usage: serve_http() without return types