class_docstr: Stores data in temp buckets, restitute it shuffled.
code: def bucket_lengths(self):
      if self._in_memory:
          return [len(self._mem_buffer)]
      return [len(b) for b in self._buckets]
  
imports: import math
  import os
  import struct
  from typing import Iterator, List, Optional
  import uuid
  from absl import logging
  import six
  from tensorflow_datasets.core import hashing
  from tensorflow_datasets.core.utils import file_utils
  from tensorflow_datasets.core.utils import type_utils
  from tensorflow_datasets.core.utils.lazy_imports_utils import tensorflow
label_desc: Use image node_id 3 for calling the Shuffler obj's underlying member method code with example usage: obj.bucket_lengths() and returns: unknown, list