code: def _get_curr_episode(self):
      return len(self._monitor.get_episode_rewards())
  
imports: import time
  import numpy
  from collections import deque
  import gym
  from gym import spaces
  from parl.env.compat_wrappers import CompatWrapper, is_gym_version_ge, V_NPRANDOM_CHANGED
  import cv2
label_desc: Use image node_id 6 for calling the TestEnv obj's underlying member method code with example usage: obj._get_curr_episode() and returns: len