How to use the whitenoise.scantree.scantree function in whitenoise

def update_files_dictionary(self, root, prefix):
        # Build a mapping from paths to the results of `os.stat` calls
        # so we only have to touch the filesystem once
        stat_cache = dict(scantree(root))
        for path in stat_cache.keys():
            relative_path = path[len(root) :]
            relative_url = relative_path.replace("\\", "/")
            url = prefix + relative_url
            self.add_file_to_dictionary(url, path, stat_cache=stat_cache)