code: def check_common_language_folder(data_folder):
      """
      Check if the data folder actually contains the CommonLanguage dataset.
  
      If not, raises an error.
  
      Returns
      -------
      None
  
      Raises
      ------
      FileNotFoundError
          If data folder doesn't contain at least two languages.
      """
  
      # Checking if at least two languages are present in the data
      if len(set(os.listdir(data_folder)) & set(LANGUAGES)) < 2:
          err_msg = f"{data_folder} must have at least two languages from CommonLanguage in it."
          raise FileNotFoundError(err_msg)
  
file_path: speechbrain/recipes/CommonLanguage/lang_id/common_language_prepare.py
imports: import os
  import csv
  import logging
  import torchaudio
  from tqdm.contrib import tzip
  from speechbrain.utils.data_utils import get_all_files
label_desc: Use image node_id 5 for calling a global function with example usage: check_common_language_folder(data_folder) without return types