code: def freeze_batch_norm(model):
      for m in model.modules():
          if isinstance(m, torch.nn.BatchNorm2d):
              m.eval()
  
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 6 for calling a global function with example usage: freeze_batch_norm(model) without return types