docs: def block_uid(value: Union[str, BlockUID, None]) -> BlockUID:
      """
      Convert value to BlockUID instance
  
      :param value: Value to convert
      :return:
      """
      if isinstance(value, BlockUID):
          return value
      elif isinstance(value, str):
          return BlockUID.from_str(value)
      elif value is None:
          return BlockUID.empty()
      else:
          raise TypeError("Cannot convert {0} to BlockUID".format(type(value)))