docs: def _unicode_handler(obj):
      """
      Transforms an unicode string into a UTF-8 equivalent.
  
      :param obj: object to transform into it's UTF-8 equivalent
      :return: the UTF-8 equivalent of the string
      """
      try:
          result = obj.isoformat()
      except AttributeError:
          raise TypeError("Unserializable object {} of type {}".format(obj,
                                                                       type(obj)))
  
      return result