code: def setup(app):
      """
      Sets the plugin up and returns configuration of the plugin.
  
      :param app: application.
      :return json description of the configuration that is needed by the plugin.
      """
      directives.register_directive("exampleinclude", ExampleInclude)
      app.connect("doctree-read", doctree_read)
      app.add_config_value("exampleinclude_sourceroot", None, "env")
      if not airflow_theme_is_available:
          # Sphinx airflow theme has its own styles.
          app.add_css_file("exampleinclude.css")
      return {
          "version": "builtin",
          "parallel_read_safe": True,
          "parallel_write_safe": True,
      }
  
imports: from __future__ import annotations
  import os
  import traceback
  from docutils import nodes
  from docutils.parsers.rst import directives
  from sphinx.directives.code import LiteralIncludeReader
  from sphinx.ext.viewcode import viewcode_anchor
  from sphinx.locale import _
  from sphinx.pycode import ModuleAnalyzer
  from sphinx.util import logging, parselinenos
  from sphinx.util.docutils import SphinxDirective
  from sphinx.util.nodes import set_source_info
label_desc: Use image node_id 4 for calling a global function with example usage: setup(app) and returns: dict