fs: fsspec.AbstractFileSystem
            path = str(url_or_filenames[0])
            if is_relative_path(path):
                # append the relative path to the base_path
                path = url_or_path_join(self._base_path, path)
            fs, path = url_to_fs(path, **download_config.storage_options)
            size = 0
            try:
                size = fs.info(path).get("size", 0)
            except Exception:
                pass
            max_workers = (
                config.HF_DATASETS_MULTITHREADING_MAX_WORKERS if size < (20 << 20) else 1
            )  # enable multithreading if files are small