code: def _collate_item(self, item):
      item = self._maybe_cast_to_list(item)
      max_length = max([len(x) for x in item]) if item else 0
      item = [
          x + [self.tokenizer.pad_id] * (max_length - len(x))
          for x in item
      ]
      return item
  
file_path: NeMo/nemo/collections/nlp/data/language_modeling/t0_dataset.py
imports: import numpy
  import torch
  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, TextMemMapDataset
  from nemo.core.classes import Dataset
label_desc: Use image node_id 7 for calling the T0Dataset obj's underlying member method code with example usage: obj._collate_item(item) and returns: item