docstr: Get ids to save.
code: def save(self):
      """
      Get ids to save.
      """
      return self._transformer.save()
  
file_path: torchrec/contrib/dynamic_embedding/src/torchrec_dynamic_embedding/id_transformer.py
imports: import json
  import os
  import torch
  from .tensor_list import TensorList
label_desc: Use image node_id 4 for calling the IDTransformer obj's underlying member method code with example usage: obj.save() and returns: self