code: def step_wait(self):
      results = [remote.recv() for remote in self.remotes]
      self.waiting = False
      obs, rews, dones, infos = zip(*results)
      return np.stack(obs), np.stack(rews), np.stack(dones), infos
  
file_path: keras-rl/rl/common/vec_env/subproc_env_vec.py
imports: import numpy
  from multiprocessing import Process, Pipe
  from rl.common.vec_env import VecEnv, CloudpickleWrapper
  from rl.common.tile_images import tile_images
label_desc: Use image node_id 3 for calling the SubprocVecEnv obj's underlying member method code with example usage: obj.step_wait() and returns: np,  np,  np,  infos