class_docstr: Base class for callback.
  
  :param verbose: (int)
class_docstr_tok: ["Base","class","for","callback",".",":","param","verbose",":","(","int",")"]
docstr: Initialize the callback by saving references to the
  RL model and the training environment for convenience.
docstr_tok: ["Initialize","the","callback","by","saving","references","to","the","RL","model","and","the","training","environment","for","convenience","."]
code: def init_callback(self, model: "BaseRLModel") -> None:
      """
      Initialize the callback by saving references to the
      RL model and the training environment for convenience.
      """
      self.model = model
      self.training_env = model.get_env()
      self.logger = logger.Logger.CURRENT
      self._init_callback()
  
imports: import os
  from abc import ABC
  import warnings
  import typing
  from typing import Union, List, Dict, Any, Optional
  import gym
  import numpy
  from stable_baselines.common.vec_env import VecEnv, sync_envs_normalization, DummyVecEnv
  from stable_baselines.common.evaluation import evaluate_policy
  from stable_baselines import logger
label_desc: Use image node_id 2 for calling the BaseCallback obj's underlying member method code with example usage: obj.init_callback(model) without return types