code: def enc_to_clear_filename(fname):
      
      if not fname.lower().endswith('.json'):
          raise CredkeepException('Invalid filetype')
  
      if not fname.lower().endswith('.enc.json'):
          raise CredkeepException('Not filename of encrypted file')
  
      clear_fname = fname.replace('.enc.json', '.json')
      print clear_fname
  
      return clear_fname if exists(clear_fname) else None
docs: Converts the filename of an encrypted file to cleartext
  
      :param fname:
      :return: filename of clear secret file if found, else None