code: def _save_old_reqs(self):
      if os.path.isfile(self._save_path):
          with codecs.open(self._save_path, "rb", "utf-8") as f:
              self._old_reqs = f.readlines()
  
file_path: clearml/clearml/utilities/pigar/__main__.py
imports: from __future__ import print_function, division, absolute_import
  import os
  import codecs
  import six
  from .reqs import project_import_modules, is_std_or_local_lib, is_base_module
  from .utils import lines_diff
  from .log import logger
  from .modules import ReqsModules
label_desc: Use image node_id 9 for calling the GenerateReqs obj's underlying member method code with example usage: obj._save_old_reqs() without return types