class_docstr: Reader object that loads the dataset from the D4RL dataset.
class_docstr_tok: ["Reader","object","that","loads","the","dataset","from","the","D4RL","dataset","."]
code: def next(self) -> SampleBatchType:
      if self.counter >= self.dataset.count:
          self.counter = 0
  
      self.counter += 1
      return self.dataset.slice(
          start=self.counter, end=self.counter + 1
      )
  
file_path: ray/python/ray/rllib/offline/d4rl_reader.py
imports: import logging
  import gymnasium
  from ray.rllib.offline.input_reader import InputReader
  from ray.rllib.offline.io_context import IOContext
  from ray.rllib.policy.sample_batch import SampleBatch
  from ray.rllib.utils.annotations import override, PublicAPI
  from ray.rllib.utils.typing import SampleBatchType
  from typing import Dict
label_desc: Use image node_id 2 for calling the D4RLReader obj's underlying member method code with example usage: obj.next() and returns: self