class_docstr: Stack previous four frames (must be applied to Gym env, not our envs).
class_docstr_tok: ["Stack","previous","four","frames","(","must","be","applied","to","Gym","env",",","not","our","envs",")","."]
docstr: Forward all other calls to the base environment.
docstr_tok: ["Forward","all","other","calls","to","the","base","environment","."]
code: def __getattr__(self, name: Text) -> Any:
      """Forward all other calls to the base environment."""
      return getattr(self._env, name)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import collections
  from typing import Any, Text
  import gym
  import numpy
  from tf_agents.environments import py_environment
  from tf_agents.environments import wrappers
  from tf_agents.trajectories import time_step
label_desc: Use image node_id 2 for calling the FrameStack4 obj's underlying member method code with example usage: obj.__getattr__(name) and returns: getattr