code: def get_browser_controller(browser: str | None = None) -> BrowserLike:
      """Return a browser controller.
  
      Args:
          browser (str or None) : browser name, or ``None`` (default: ``None``)
              If passed the string ``'none'``, a dummy web browser controller
              is returned.
  
              Otherwise, use the value to select an appropriate controller using
              the :doc:`webbrowser <python:library/webbrowser>` standard library
              module. If the value is ``None``, a system default is used.
  
      Returns:
          controller : a web browser controller
  
      """
      browser = settings.browser(browser)
  
      if browser is None:
          controller = cast(BrowserLike, webbrowser)
      elif browser == "none":
          controller = DummyWebBrowser()
      else:
          controller = webbrowser.get(browser)
  
      return controller
  
file_path: bokeh/src/bokeh/util/browser.py
imports: from __future__ import annotations
  import logging
  import webbrowser
  from os.path import abspath
  from typing import Literal, Protocol, cast
  from ..settings import settings
label_desc: Use image node_id 1 for calling a global function with example usage: get_browser_controller(browser) and returns: controller