code: def _get_bn_stats(self, model):
      model = copy.deepcopy(model)
      stats = {}
      for name, module in model.named_modules():
          if isinstance(module, nn.modules.batchnorm._BatchNorm):
              stats[name] = {
                  "mean": module.running_mean,
                  "var": module.running_var,
              }
      return stats
  
file_path: ClassyVision/test/hooks_precise_batch_norm_hook_test.py
imports: import copy
  import torch
  import torch.nn
  from classy_vision.hooks import ClassyHook
  from classy_vision.hooks.precise_batch_norm_hook import PreciseBatchNormHook
  from classy_vision.tasks import build_task
  from classy_vision.trainer import ClassyTrainer
  from test.generic.config_utils import get_test_mlp_task_config
  from test.generic.hook_test_utils import HookTestBase
label_desc: Use image node_id 1 for calling the TestPreciseBatchNormHook obj's underlying member method code with example usage: obj._get_bn_stats(model) and returns: stats