code: def _load_optimizer(self, ckpt):
      if "optimizer" in ckpt:
          try:
              self.trainer.optimizer.load_state_dict(ckpt["optimizer"])
          except ValueError:
              logger.info(
                  "Optimizer failed to load. Try with "
                  + "checkpoint.reset.optimizer=True"
              )
              raise
      else:
          warnings.warn(
              "'optimizer' key is not present in the "
              "checkpoint asked to be loaded. Skipping."
          )
  
imports: import glob
  import importlib
  import logging
  import os
  import sys
  import warnings
  from typing import Any, Dict
  import torch
  from mmf.common.registry import registry
  from mmf.utils.checkpoint_updater import get_pretrained_state_mapping_checkpoint
  from mmf.utils.configuration import get_mmf_env, load_yaml
  from mmf.utils.distributed import is_main, is_xla, open_if_main, synchronize
  from mmf.utils.download import download_pretrained_model
  from mmf.utils.file_io import PathManager
  from mmf.utils.general import get_current_device, updir
  from mmf.utils.xla import save_xla_ckpt
  from omegaconf import OmegaConf
label_desc: Use image node_id 6 for calling the Checkpoint obj's underlying member method code with example usage: obj._load_optimizer(ckpt) without return types