docstr: Return only every `skip`-th frame
docstr_tok: ["Return","only","every","`","skip","`","-th","frame"]
code: def __init__(self, env, skip=4):
      """Return only every `skip`-th frame"""
      gym.Wrapper.__init__(self, env)
      # most recent raw observations (for max pooling across time steps)
      self._obs_buffer = np.zeros(
          (2,) + env.observation_space.shape, dtype=np.uint8
      )
      self._skip = skip
  
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 1 to create a new MaxAndSkipEnv object from inherited base classes: gym with example: obj = MaxAndSkipEnv(env, skip)