code: def setup(app):
      """Required Sphinx extension setup function."""
      app.add_directive_to_domain(
          "py", "bokeh-enum", BokehEnumDirective
      )
  
      return PARALLEL_SAFE
  
file_path: bokeh/src/bokeh/sphinxext/bokeh_enum.py
imports: from __future__ import annotations
  import logging
  import importlib
  import textwrap
  from docutils.parsers.rst.directives import unchanged
  from sphinx.errors import SphinxError
  from .None import PARALLEL_SAFE
  from .bokeh_directive import BokehDirective
  from .templates import ENUM_DETAIL
label_desc: Use image node_id 1 for calling a global function with example usage: setup(app) and returns: PARALLEL_SAFE