code: def reset(self):
      self.sum = None
      self.count = 0
  
imports: import logging
  import os
  import sys
  import time
  import horovod.mxnet
  import mxnet
  from mxboard import SummaryWriter
  from mxnet import nd
  from default import config
  from evaluation import verification
label_desc: Use image node_id 2 for calling the MetricNdarray obj's underlying member method code with example usage: obj.reset() without return types