@classmethod
def _path_importer_cache(cls, path):
    """Get the finder for the path entry from sys.path_importer_cache.

    If the path entry is not in the cache, find the appropriate finder
    and cache it. If no finder is available, store None.

    """
    if path == '':
        try:
            path = _os.getcwd()
        except FileNotFoundError:
            # Don't cache the failure as the cwd can easily change to
            # a valid directory later on.
            return None
    try:
        finder = sys.path_importer_cache[path]
    except KeyError:
        finder = cls._path_hooks(path)
        sys.path_importer_cache[path] = finder
    return finder