code: def send(self, header, body):
          
          message = MsgProto(EMsg.ClientToGC)
          message.header.routing_appid = self.app_id
          message.body.appid = self.app_id
          message.body.msgtype = (set_proto_bit(header.msg)
                                  if header.proto
                                  else header.msg
                                  )
          message.body.payload = header.serialize() + body
          self.steam.send(message)
docs: Send a message to GC
  
          :param header: message header
          :type header: :class:`steam.core.msg.GCMsgHdr`
          :param body: serialized body of the message
          :type body: :class:`bytes`