code: def _maybe_cast_to_list(self, x):
      return [
          item.tolist() if isinstance(item, np.ndarray) else item
          for item in x
      ]
  
imports: import re
  from typing import List, Mapping, Optional
  import datasets
  import numpy
  import torch
  from datasets import load_dataset
  from nemo.collections.common.tokenizers.tokenizer_spec import TokenizerSpec
  from nemo.collections.nlp.data.language_modeling.megatron.dataset_utils import get_samples_mapping
  from nemo.collections.nlp.data.language_modeling.text_memmap_dataset import JSONLMemMapDataset
  from nemo.core.classes import Dataset
  from nemo.utils import logging
label_desc: Use image node_id 6 for calling the GPTSFTPackedDataset obj's underlying member method code with example usage: obj._maybe_cast_to_list(x) and returns: unknown