code: def old_unpad(s):
      
      if not s:
          return s
  
      try:
          return Padding.removePadding(s, blocksize=OLD_BLOCK_SIZE)
      except AssertionError:
          # if there's an error while removing padding, just return s.
          return s
docs: Removes padding from an input string based on a given block size.
      :param s: string
      :returns: The unpadded string.