code: def __init__(self):
      self.counter = 0
  
file_path: ray/python/ray/tune/tests/test_callbacks.py
imports: import pytest
  from typing import Dict, Optional
  from ray.tune.callback import Callback, CallbackList
label_desc: Use image node_id 1 to create a new StatefulCallback object from inherited base classes: Callback with example: obj = StatefulCallback()