code: def _os_lstat(self, filename):
      f = self._lookup_mock_fs(filename)
      mode = stat.S_IFDIR if isinstance(f, dict) else stat.S_IFREG
      return namedtuple("fake_stat_type", "st_mode")(st_mode=mode)
  
imports: import stat
  import unittest
  import yaml
  from collections import namedtuple
  from unittest.mock import patch
  from parameterized import parameterized
  import __res
label_desc: Use image node_id 7 for calling the ImporterMocks obj's underlying member method code with example usage: obj._os_lstat(filename) and returns: namedtuple