code: def _classify_directory_contents(filesystem, root):
      
      dirs = []
      files = []
      for entry in filesystem.listdir(root):
          if filesystem.isdir(filesystem.joinpaths(root, entry)):
              dirs.append(entry)
          else:
              files.append(entry)
      return root, dirs, files
docs: Classify contents of a directory as files/directories.
  
      Args:
          filesystem: The fake filesystem used for implementation
          root: (str) Directory to examine.
  
      Returns:
          (tuple) A tuple consisting of three values: the directory examined,
          a list containing all of the directory entries, and a list
          containing all of the non-directory entries.
          (This is the same format as returned by the `os.walk` generator.)
  
      Raises:
          Nothing on its own, but be ready to catch exceptions generated by
          underlying mechanisms like `os.listdir`.