code: def default_local_cache_dir(self) -> Optional[str]:
      repo = self._repo
      if repo and repo.local_dvc_dir:
          return os.path.join(repo.local_dvc_dir, self.CACHE_DIR)
      return None
  
file_path: dvc/dvc/cachemgr.py
imports: import os
  from typing import TYPE_CHECKING, Optional, Tuple
  from dvc.fs import GitFileSystem, Schemes
  from dvc_data.hashfile.db import get_odb
  from dvc_data.hashfile.hash import DEFAULT_ALGORITHM
label_desc: Use image node_id 7 for calling the CacheManager obj's underlying member method code with example usage: obj.default_local_cache_dir() and returns: None, os