code: def on_sample_end(self, *args, **kwargs):
      self.counts.update({"sample": 1})
  
imports: from collections import Counter
  import unittest
  import ray
  from ray.rllib.algorithms.callbacks import DefaultCallbacks
  from ray.rllib.algorithms.ppo import PPOConfig
  from ray.rllib.env.single_agent_env_runner import SingleAgentEnvRunner
  from ray.rllib.utils.test_utils import framework_iterator
label_desc: Use image node_id 6 for calling the EpisodeAndSampleCallbacks obj's underlying member method code with example usage: obj.on_sample_end() without return types