code: def _check_voxceleb_folders(data_folders, splits):
      """
      Check if the data folder actually contains the Voxceleb1 dataset.
  
      If it does not, raise an error.
  
      Returns
      -------
      None
  
      Raises
      ------
      FileNotFoundError
      """
      for data_folder in data_folders:
          if "train" in splits:
              folder_vox1 = os.path.join(data_folder, "wav", "id10001")
              folder_vox2 = os.path.join(data_folder, "wav", "id00012")
  
              if not os.path.exists(folder_vox1) or not os.path.exists(
                  folder_vox2
              ):
                  err_msg = (
                      "the specified folder does not contain Voxceleb"
                  )
                  raise FileNotFoundError(err_msg)
  
          if "test" in splits:
              folder = os.path.join(data_folder, "wav", "id10270")
              if not os.path.exists(folder):
                  err_msg = (
                      "the folder %s does not exist (as it is expected in "
                      "the Voxceleb dataset)" % folder
                  )
                  raise FileNotFoundError(err_msg)
  
          folder = os.path.join(data_folder, "meta")
          if not os.path.exists(folder):
              err_msg = (
                  "the folder %s does not exist (as it is expected in "
                  "the Voxceleb dataset)" % folder
              )
              raise FileNotFoundError(err_msg)
  
file_path: speechbrain/recipes/VoxCeleb/SpeakerRec/voxceleb_prepare.py
imports: import os
  import csv
  import logging
  import glob
  import random
  import shutil
  import sys
  import numpy
  import torch
  import torchaudio
  from tqdm.contrib import tqdm
  from speechbrain.dataio.dataio import load_pkl, save_pkl
label_desc: Use image node_id 3 for calling a global function with example usage: _check_voxceleb_folders(data_folders, splits) without return types