D2 packets reconstruct

 def ParsePacket(self, packet_data, sender, action):
        packet = Packet()
        if self.reconstruct and not self.oldpacket == None and self.oldpacket.send == sender:
            new = packet_data
            packet.RecvPacket(self.oldpacket.fullpacket + new, sender, action)
            self.reconstruct = False
            self.oldpacket = None
        else:
            packet.RecvPacket(packet_data, sender, action)

        if self.oldpacket != None and self.oldpacket.send != sender:
            self.reconstruct = False
            self.oldpacket = None

        while packet.len < len(packet.data):
            extracted_data = packet.fullpacket[0 : packet.len + packet.size_len + 2 + (4 if sender else 0)]
            goodPacket = Packet()
            goodPacket.RecvPacket(extracted_data, sender, action)
            goodPacket.Deserialize(Reader(goodPacket.data))

            nextdata = packet.fullpacket[packet.len + packet.size_len + 2 + (4 if sender else 0):]
            packet = Packet()
            if packet.RecvPacket(nextdata, sender, action) == False:
                self.oldpacket = packet
                self.reconstruct = True
                return
            if packet.len == 0:
                packet.Deserialize(Reader(b""))
                data = packet.fullpacket[2 + (4 if sender else 0):]
                if len(data) > 0:
                    packet = Packet()
                    packet.RecvPacket(data, sender, action)
                else:
                    return

        if len(packet.data) > packet.len:
            print("[-] ERROR")
        elif len(packet.data) == packet.len:
            packet.action = action
            packet.Deserialize(Reader(packet.data))
        else:
            self.oldpacket = packet
            self.reconstruct = True