code: def normalize(self, batch):
      batch = (batch - self.mean) / (self.std + 1e-15)
      return np.clip(batch, *self.clip_values)
  
imports: import os
  from abc import ABC, abstractmethod
  import threading
  import pickle
  import redis
  import numpy
  from rl_coach.utils import get_latest_checkpoint
label_desc: Use image node_id 9 for calling the NumpySharedRunningStats obj's underlying member method code with example usage: obj.normalize(batch) and returns: np