code: def _is_raw_file(fileobj):
      """Check if fileobj is a raw file object, e.g created with open."""
      if PY3_OR_LATER:
          fileobj = getattr(fileobj, "raw", fileobj)
          return isinstance(fileobj, io.FileIO)
      else:
          return isinstance(fileobj, file)
  
imports: import pickle
  import sys
  import io
  import zlib
  import gzip
  import warnings
  import contextlib
  from contextlib import closing
  from ._compat import PY3_OR_LATER, PY27, _basestring
label_desc: Use image node_id 1 for calling a global function with example usage: _is_raw_file(fileobj) and returns: isinstance, isinstance