code: def check(app, exception):
      missing_entities = []
  
      missing_entities += [
          name
          for name in _list_chainer_functions()
          if not _is_rst_exists(name)
      ]
  
      missing_entities += [
          name
          for name in _list_chainer_links()
          if not _is_rst_exists(name)
      ]
  
      if missing_entities:
          logger.warning(
              "\n".join(
                  [
                      "Undocumented entities found.",
                      "",
                  ]
                  + missing_entities
              )
          )
  
file_path: chainer/docs/source/_autosummary_check.py
imports: import inspect
  import os
  import types
  import sphinx
  import chainer.functions
  import chainer.links
label_desc: Use image node_id 2 for calling a global function with example usage: check(app, exception) without return types