code: def update_checkpoint(self):
      while self.version != SavedCalamariModel.VERSION:
          if SavedCalamariModel.VERSION < self.version:
              raise Exception(
                  "Downgrading of models is not supported ({} to {}). Please upgrade your Calamari "
                  "instance (currently installed: {})".format(
                      self.version,
                      SavedCalamariModel.VERSION,
                      __version__,
                  )
              )
          self._single_upgrade()
  
      logger.info(
          f"Successfully upgraded checkpoint version to {SavedCalamariModel.VERSION}"
      )
  
file_path: calamari/calamari_ocr/ocr/savedmodel/saved_model.py
imports: import shutil
  import json
  import os
  import logging
  import packaging.version
  from calamari_ocr import __version__
  from calamari_ocr.utils import split_all_ext
label_desc: Use image node_id 2 for calling the SavedCalamariModel obj's underlying member method code with example usage: obj.update_checkpoint() without return types