code: def __str__(self):
      loss_str = []
      for name, meter in self.meters.items():
          loss_str.append(f"{name}: {str(meter)}")
      return self.delimiter.join(loss_str)
  
imports: import datetime
  import os
  import time
  from collections import defaultdict, deque
  import torch
  import torch.distributed
  import torch.nn.functional
label_desc: Use image node_id 4 for calling the MetricLogger obj's underlying member method code with example usage: obj.__str__() and returns: self