code: def get_checkpoint_save_function(self):
      return self.checkpoint_save_function
  
imports: import datetime
  import os
  import signal
  import sys
  import time
  import traceback
  from subprocess import call
  from .argparse_hopt import HyperOptArgumentParser
label_desc: Use image node_id 3 for calling the AbstractCluster obj's underlying member method code with example usage: obj.get_checkpoint_save_function() and returns: self