code: def _is_raw_file(fileobj):
      """Check if fileobj is a raw file object, e.g created with open."""
      fileobj = getattr(fileobj, "raw", fileobj)
      return isinstance(fileobj, io.FileIO)
  
file_path: catboost/contrib/python/joblib/joblib/numpy_pickle_utils.py
imports: import pickle
  import io
  import sys
  import warnings
  import contextlib
  from .compressor import _ZFILE_PREFIX
  from .compressor import _COMPRESSORS
label_desc: Use image node_id 1 for calling a global function with example usage: _is_raw_file(fileobj) and returns: isinstance