code: def unwrap_model(self) -> nn.Module:
      return self.model
  
imports: import warnings
  from pathlib import Path
  from typing import Callable, Iterable, Iterator, List, Optional, Tuple
  import torch
  import torch.nn
  from packaging import version
  from torch.distributed import ProcessGroup
  from torch.optim import Optimizer
  from torch.optim.lr_scheduler import _LRScheduler
  from torch.utils.data import DataLoader
  from colossalai.checkpoint_io import CheckpointIO, GeneralCheckpointIO, utils
  from colossalai.cluster import DistCoordinator
  from colossalai.interface import ModelWrapper, OptimizerWrapper
  from .dp_plugin_base import DPPluginBase
label_desc: Use image node_id 2 for calling the FSDPOptimizerWrapper obj's underlying member method code with example usage: obj.unwrap_model() and returns: self