code: def step(self, actions):
      
      self._elapsed_steps += 1
      obs, rewards, dones = \
          [np.array(r) for r in self.batch_env.step(actions)]
      if self._elapsed_steps > self._max_episode_steps:
        done = True
        if self._elapsed_steps > self._max_episode_steps + 1:
          rewards.fill(0)
      else:
        done = dones[0]
        assert np.all(done == dones), ("Current modifications of Dopamine "
                                       "require same number of steps for each "
                                       "environment in batch")
        del dones
  
      self.game_over = done
      return obs, rewards, done, {}
docs: Step.