code: def save(self, checkpoint_path: pathlib.Path) -> any:
      data = {
          key: infoset.to_dict()
          for key, infoset in self.infosets.items()
      }
      file_name = f"infosets.json"
  
      with open(str(checkpoint_path / file_name), "w") as f:
          f.write(json.dumps(data))
  
      return file_name
  
file_path: annotated_deep_learning_paper_implementations/labml_nn/cfr/infoset_saver.py
imports: import json
  import pathlib
  from typing import Dict
  from labml import experiment
  from labml_nn.cfr import InfoSet
label_desc: Use image node_id 2 for calling the InfoSetSaver obj's underlying member method code with example usage: obj.save(checkpoint_path) and returns: file_name