code: def data_index(self) -> "DataIndex":
      from dvc_data.index import DataIndex
  
      if self._data_index is None:
          index_dir = os.path.join(self.site_cache_dir, "index", "data")
          os.makedirs(index_dir, exist_ok=True)
          self._data_index = DataIndex.open(
              os.path.join(index_dir, "db.db")
          )
  
      return self._data_index
  
imports: import os
  from collections import defaultdict
  from contextlib import contextmanager
  from functools import wraps
  from typing import TYPE_CHECKING, Callable, ContextManager, Iterable, Optional, Tuple, Union
  from dvc.exceptions import DvcException, NotDvcRepoError, OutputNotFoundError, RevCollectionError
  from dvc.ignore import DvcIgnoreFilter
  from dvc.log import logger
  from dvc.utils.objects import cached_property
label_desc: Use image node_id 17 for calling the Repo obj's underlying member method code with example usage: obj.data_index() and returns: self