code: def __call__(self, global_step, epoch, backbone, is_consistent=False):
      if global_step > 100 and backbone is not None:
          path_module = os.path.join(self.output, "epoch_%d" % (epoch))
  
          if is_consistent:
              flow.save(
                  backbone.state_dict(),
                  path_module,
                  consistent_dst_rank=0,
              )
          else:
              if self.rank == 0:
                  flow.save(backbone.state_dict(), path_module)
          logging.info(
              "oneflow Model Saved in '{}'".format(path_module)
          )
  
imports: import logging
  import os
  import time
  from typing import List
  import oneflow
  from eval import verification
  from utils.utils_logging import AverageMeter
label_desc: Use image node_id 2 for calling the CallBackModelCheckpoint obj's underlying member method code with example usage: obj.__call__(global_step, epoch, backbone, is_consistent) without return types