class_docstr: The low-level interface dataset class
  
  Args:
      path_prefix (str): The index (.idx) and data (.bin) prefix
  
      multimodal (bool, optional): Whether the dataset is multimodal. Defaults to False.
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docstr: Return whether the MMapIndexedDataset exists on disk at the prefix
  
  Args:
      path_prefix (str): The prefix to the index (.idx) and data (.bin) files
  
  Returns:
      bool: Whether the MMapIndexedDataset exists on disk at the prefix
docstr_tok: ["Return","whether","the","MMapIndexedDataset","exists","on","disk","at","the","prefix","Args",":","path_prefix","(","str",")",":","The","prefix","to","the","index","(",".idx",")","and","data","(",".bin",")","files","Returns",":","bool",":","Whether","the","MMapIndexedDataset","exists","on","disk","at","the","prefix"]
code: def exists(path_prefix: str) -> bool:
      """Return whether the MMapIndexedDataset exists on disk at the prefix
  
      Args:
          path_prefix (str): The prefix to the index (.idx) and data (.bin) files
  
      Returns:
          bool: Whether the MMapIndexedDataset exists on disk at the prefix
      """
      return os.path.exists(
          get_idx_path(path_prefix)
      ) and os.path.exists(get_bin_path(path_prefix))
  
imports: import logging
  import os
  import shutil
  import struct
  import time
  from enum import Enum
  from functools import lru_cache
  from itertools import accumulate
  from types import TracebackType
  from typing import List, Optional, Tuple, Type, Union
  import numpy
  import torch
  from megatron.core.datasets.utils import log_single_rank
label_desc: Use image node_id 14 for calling the MMapIndexedDataset obj's underlying member method code with example usage: obj.exists(path_prefix) and returns: unknown