code: def push(self, request):
          
          data = self._encode_request(request)
          score = -request.priority
          # We don't use zadd method as the order of arguments change depending on
          # whether the class is Redis or StrictRedis, and the option of using
          # kwargs only accepts strings, not bytes.
          self.server.execute_command('ZADD', self.key, score, data)
docs: Push a request