code: def step(self, actions):
      
  
      observations, raw_rewards, dones, infos = self._step(actions)
  
      # Process rewards.
      raw_rewards = raw_rewards.astype(np.float32)
      processed_rewards = self.process_rewards(raw_rewards)
  
      # Process observations.
      processed_observations = self.process_observations(observations)
  
      # Record history.
      self.trajectories.step(processed_observations, raw_rewards,
                             processed_rewards, dones, actions)
  
      return processed_observations, processed_rewards, dones, infos
docs: Takes a step in all environments.
  
      Subclasses should override _step to do the actual reset if something other
      than the default implementation is desired.
  
      Args:
        actions: Batch of actions.
  
      Returns:
        (preprocessed_observations, processed_rewards, dones, infos).