code: def __iter__(self):
      if self.seed is None:
          random.seed(self.epoch)
          self.epoch += 1
      else:
          random.seed(self.seed)
      random.shuffle(self.batchs_in_one_epoch_id)
      for batch_tuple_id in self.batchs_in_one_epoch_id:
          yield self.batchs_in_one_epoch[batch_tuple_id]
  
file_path: PaddleOCR/ppocr/data/multi_scale_sampler.py
imports: from paddle.io import Sampler
  import paddle.distributed
  import numpy
  import random
  import math
label_desc: Use image node_id 2 for calling the MultiScaleSampler obj's underlying member method code with example usage: obj.__iter__() without return types