code: def _pack_gelf_dict(gelf_dict):
          
          gelf_dict = BaseGELFHandler._sanitize_to_unicode(gelf_dict)
          packed = json.dumps(
              gelf_dict,
              separators=',:',
              default=BaseGELFHandler._object_to_json
          )
          return packed.encode('utf-8')
docs: Convert a given ``gelf_dict`` to a JSON-encoded string, thus,
          creating an uncompressed GELF log ready for consumption by Graylog.
  
          Since we cannot be 100% sure of what is contained in the ``gelf_dict``
          we have to do some sanitation.
  
          :param gelf_dict: dictionary representation of a GELF log.
          :type gelf_dict: dict
  
          :return: A prepped JSON-encoded GELF log as a bytes string
              encoded in UTF-8.
          :rtype: bytes