class_docstr: Hook function that will be called after evaluation.
  
  Every evaluation hook function must inherit this class.
  
  Attributes:
      support_train_agent (bool):
          Set to ``True`` if the hook can be used in
          pfrl.experiments.train_agent.train_agent_with_evaluation.
      support_train_agent_batch (bool):
          Set to ``True`` if the hook can be used in
          pfrl.experiments.train_agent_batch.train_agent_batch_with_evaluation.
      support_train_agent_async (bool):
          Set to ``True`` if the hook can be used in
          pfrl.experiments.train_agent_async.train_agent_async.
docstr: Call the hook.
  
  Args:
      env: Environment.
      agent: Agent.
      evaluator: Evaluator.
      step: Current timestep. (Not the number of evaluations so far)
      eval_stats (dict): Last evaluation stats from
          pfrl.experiments.evaluator.eval_performance().
      agent_stats (List of pairs): Last agent stats from
          agent.get_statistics().
      env_stats: Last environment stats from
          env.get_statistics().
docstr_tok: ["Call","the","hook",".","Args",":","env",":","Environment",".","agent",":","Agent",".","evaluator",":","Evaluator",".","step",":","Current","timestep",".","(","Not","the","number","of","evaluations","so","far",")","eval_stats","(","dict",")",":","Last","evaluation","stats","from","pfrl.experiments.evaluator.eval_performance","(",")",".","agent_stats","(","List","of","pairs",")",":","Last","agent","stats","from","agent.get_statistics","(",")",".","env_stats",":","Last","environment","stats","from","env.get_statistics","(",")","."]
code: def __call__(
      self,
      env,
      agent,
      evaluator,
      step,
      eval_stats,
      agent_stats,
      env_stats,
  ):
      """Call the hook.
  
      Args:
          env: Environment.
          agent: Agent.
          evaluator: Evaluator.
          step: Current timestep. (Not the number of evaluations so far)
          eval_stats (dict): Last evaluation stats from
              pfrl.experiments.evaluator.eval_performance().
          agent_stats (List of pairs): Last agent stats from
              agent.get_statistics().
          env_stats: Last environment stats from
              env.get_statistics().
      """
      raise NotImplementedError
  
imports: from abc import ABCMeta, abstractmethod
label_desc: Use image node_id 1 for calling the EvaluationHook obj's underlying member method code with example usage: obj.__call__(env, agent, evaluator, step, eval_stats, agent_stats, env_stats) without return types