code: def _iter_dirs(root):
      try:
          names = os.listdir(root)
      except OSError:
          names = []
      for name in names:
          path = os.path.join(root, name)
          if _opref_exists(path):
              yield name, path
  
imports: import errno
  import functools
  import logging
  import os
  import shutil
  import tempfile
  from guild import config
  from guild import run
  from guild import util
label_desc: Use image node_id 19 for calling a global function with example usage: _iter_dirs(root) without return types