code: def aggregate_sub_bn_stats(module):
      """
      Recursively find all SubBN modules and aggregate sub-BN stats.
      Args:
          module (nn.Module)
      Returns:
          count (int): number of SubBN module found.
      """
      count = 0
      for child in module.children():
          if isinstance(child, SubBatchNorm3d):
              child.aggregate_stats()
              count += 1
          else:
              count += aggregate_sub_bn_stats(child)
      return count
  
imports: import json
  import logging
  import math
  import numpy
  import os
  from datetime import datetime
  import psutil
  import torch
  import torchvision.io
  from fvcore.nn.activation_count import activation_count
  from fvcore.nn.flop_count import flop_count
  from matplotlib import pyplot
  from torch import nn
  from torchvision.utils import make_grid
  import slowfast.utils.logging
  import slowfast.utils.multiprocessing
  from slowfast.datasets.utils import pack_pathway_output
  from slowfast.models.batchnorm_helper import SubBatchNorm3d
  from slowfast.utils.env import pathmgr
label_desc: Use image node_id 13 for calling a global function with example usage: aggregate_sub_bn_stats(module) and returns: count