code: def test_env_resources(ManagedServerLoop: MSL) -> None:
      with envset(BOKEH_RESOURCES="cdn"):
          application = Application()
          with ManagedServerLoop(application) as server:
              r = server._tornado.resources()
              assert r.mode == "cdn"
  
imports: from __future__ import annotations
  import pytest
  import json
  import logging
  from _util_server import http_get, url
  from tornado.web import StaticFileHandler
  from bokeh.application import Application
  from bokeh.client import pull_session
  from bokeh.core.types import ID
  from bokeh.server.auth_provider import NullAuth
  from bokeh.server.views.static_handler import StaticHandler
  from bokeh.server.views.ws import WSHandler
  from tests.support.plugins.managed_server_loop import MSL
  from tests.support.util.env import envset
  import bokeh.server.tornado
label_desc: Use image node_id 2 for calling a global function with example usage: test_env_resources(ManagedServerLoop) without return types