code: def data_cache_dir(self) -> str:
      return os.path.join(self.cache_dir, "data")
  
file_path: carefree-learn/cflearn/parameters.py
imports: import os
  from typing import Any
  from typing import Dict
  from cftool.misc import OPTBase
label_desc: Use image node_id 3 for calling the OPTClass obj's underlying member method code with example usage: obj.data_cache_dir() and returns: os