code: def ipe(self):
      return (
          self.num_classes // self.cpb
          if not self.unique_cpb
          else self.num_classes // (self.cpb * self.world_size)
      )
  
imports: import contextlib
  import logging
  import queue
  from typing import Dict, List
  import numpy
  import torch
  from PIL import Image
  from torch.utils.data import Dataset
  from torch.utils.data.distributed import DistributedSampler
label_desc: Use image node_id 11 for calling the StratifiedClassSampler obj's underlying member method code with example usage: obj.ipe() and returns: unknown