code: def to_bytes(self, inst_data, encoding=None):
          
          selected = encoding or self.default_encoding
          content_type = '{0}; charset="{1}"'.format(self.content_type, selected)
          dumped = self._dumps(escape.recursive_unicode(inst_data))
          return content_type, dumped.encode(selected)
docs: Transform an object into :class:`bytes`.
  
          :param object inst_data: object to encode
          :param str encoding: character set used to encode the bytes
              returned from the ``dumps`` function.  This defaults to
              :attr:`default_encoding`
          :returns: :class:`tuple` of the selected content
              type and the :class:`bytes` representation of
              `inst_data`