code: def _save_extra(
      self, extra_array: np.ndarray, extra_path: str
  ) -> None:
      extra_root = self._extra_root
      extra_full_path = os.path.join(extra_root, extra_path)
      os.makedirs(extra_root, exist_ok=True)
      np.save(extra_full_path, extra_array)
  
imports: from dataclasses import dataclass
  from enum import Enum
  from functools import lru_cache
  from gzip import GzipFile
  from io import BytesIO
  from mmap import ACCESS_READ, mmap
  import os
  from typing import Any, Callable, List, Optional, Set, Tuple
  import warnings
  import numpy
  from .extended import ExtendedVisionDataset
label_desc: Use image node_id 7 for calling the ImageNet22k obj's underlying member method code with example usage: obj._save_extra(extra_array, extra_path) without return types