docstr: Called on every worker immediately after a new best model is checkpointed.
docstr_tok: ["Called","on","every","worker","immediately","after","a","new","best","model","is","checkpointed","."]
code: def on_save_best_checkpoint(
      self, trainer, progress_tracker, save_path
  ):
      """Called on every worker immediately after a new best model is checkpointed."""
      pass
  
imports: from abc import ABC
  from typing import Any, Callable, Dict, List, Union
  from ludwig.api_annotations import PublicAPI
  from ludwig.types import HyperoptConfigDict, ModelConfigDict, TrainingSetMetadataDict
label_desc: Use image node_id 31 for calling the Callback obj's underlying member method code with example usage: obj.on_save_best_checkpoint(trainer, progress_tracker, save_path) without return types