code: def update(self, x):
      batch_mean = torch.mean(x, axis=0)
      batch_var = torch.var(x, axis=0)
      batch_count = x.shape[0]
      self.mean, self.var, self.count = _mean_var_count_from_moments(
          self.mean,
          self.var,
          self.count,
          batch_mean,
          batch_var,
          batch_count,
      )
  
imports: import copy
  import dataclasses
  import logging
  import torch
  import moolib
label_desc: Use image node_id 2 for calling the RunningMeanStd obj's underlying member method code with example usage: obj.update(x) without return types