code: def optionally_index(self, model_dict):
      if self.subkey is not None:
          return model_dict[self.subkey]
      return model_dict
  
imports: from dataclasses import dataclass
  from enum import Enum
  from typing import Callable, Optional
  import torch
  import torch.nn
  import torch.nn.functional
  import torch.nn.utils.parametrize
label_desc: Use image node_id 1 for calling the VocType obj's underlying member method code with example usage: obj.optionally_index(model_dict) and returns: model_dict, model_dict