code: def push(self, x):
      self.n += 1
  
      if self.n == 1:
          self.old_m = self.new_m = x
          self.old_s = 0
      else:
          self.new_m = self.old_m + (x - self.old_m) / self.n
          self.new_s = self.old_s + (x - self.old_m) * (x - self.new_m)
  
          self.old_m = self.new_m
          self.old_s = self.new_s
  
imports: import numpy
label_desc: Use image node_id 3 for calling the RunningStats obj's underlying member method code with example usage: obj.push(x) without return types