code: def display(self, step):
      self.batch_time.update(time.time() - self.end)
      self.end = time.time()
      if step % self.print_freq == 0:
          self.progress.display(step)
  
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 LossTracker obj's underlying member method code with example usage: obj.display(step) without return types