class_docstr: DatasetBuilder for rlu_rwrl dataset.
class_docstr_tok: ["DatasetBuilder","for","rlu_rwrl","dataset","."]
code: def num_shards(self):
      try:
          return self._SHARDS  # For testing.  # type: ignore
      except AttributeError:
          pass
      domain = self.builder_config.domain
      combined_challenge = self.builder_config.combined_challenge
      dataset_size = self.builder_config.dataset_size
      return SHARDS_MAPPING[(combined_challenge, domain, dataset_size)]
  
imports: from __future__ import annotations
  import collections
  import dataclasses
  import functools
  import os
  from typing import Any, Dict, Generator, Optional, Sequence, Text, Tuple, Union
  import numpy
  from tensorflow_datasets.core.utils.lazy_imports_utils import tensorflow
  import tensorflow_datasets.public_api
  from tensorflow_datasets.rl_unplugged import rlu_common
label_desc: Use image node_id 5 for calling the RluRwrl obj's underlying member method code with example usage: obj.num_shards() and returns: SHARDS_MAPPING, self