class_docstr: Computes and stores the average and current value
code: def update(self, val, n=1):
      self.val = val
      self.sum += val * n
      self.count += n
      self.avg = self.sum / self.count
  
imports: import collections
  import torch
  from torch import Tensor
  import torch.nn
  import torch.backends.cudnn
  import subprocess
  import os
  import time
  import shutil
  from datetime import datetime
  import torch.optim
  from torch.optim import lr_scheduler
  import sys
  import models
  import numpy
  import torch.nn
  import math
label_desc: Use image node_id 3 for calling the AverageMeter obj's underlying member method code with example usage: obj.update(val, n) without return types