code: def skip(annotations):
      """
      Detects if the timit data_preparation has been already done.
      If the preparation has been done, we can skip it.
  
      Returns
      -------
      bool
          if True, the preparation phase can be skipped.
          if False, it must be done.
      """
      skip = True
  
      for annotation in annotations:
          if not os.path.isfile(annotation):
              skip = False
              break
  
      return skip
  
file_path: speechbrain/recipes/TIMIT/Alignment/timit_prepare.py
imports: import os
  import json
  import logging
  from speechbrain.utils.data_utils import get_all_files
  from speechbrain.dataio.dataio import read_audio
label_desc: Use image node_id 4 for calling a global function with example usage: skip(annotations) and returns: skip