使用pcap模板时的ipv6Packet错误

尝试使用python中的Kaitai Struct读取pcap。

我已经从该js pcap.ksy 文
件创建了python 文件

$ ./bin/kaitai-struct-compiler -t python  --outdir xx formats/network/pcap.ksy 
$ ls xx
ethernet_frame.py  ipv6_packet.py  __pycache__
icmp_packet.py     packet_ppi.py   tcp_segment.py
ipv4_packet.py     pcap.py         udp_datagram.py

PYTHONPATH设置为xx目录。现在，如果我运行一个简单的单行脚本来检查是否可以加载模块

from pcap import Pcap

我得到这个错误

$ python3 try.py 
Traceback (most recent call last):
  File "try.py", line 1, in <module>
    from pcap import Pcap
  File "/spare/tmp/scratch/kaitai-struct-compiler-0.8/xx/pcap.py", line 11, in <module>
    from packet_ppi import PacketPpi
  File "/spare/tmp/scratch/kaitai-struct-compiler-0.8/xx/packet_ppi.py", line 11, in <module>
    from ethernet_frame import EthernetFrame
  File "/spare/tmp/scratch/kaitai-struct-compiler-0.8/xx/ethernet_frame.py", line 11, in <module>
    from ipv6_packet import Ipv6Packet
  File "/spare/tmp/scratch/kaitai-struct-compiler-0.8/xx/ipv6_packet.py", line 12, in <module>
    from ipv4_packet import Ipv4Packet
  File "/spare/tmp/scratch/kaitai-struct-compiler-0.8/xx/ipv4_packet.py", line 13, in <module>
    from ipv6_packet import Ipv6Packet
ImportError: cannot import name 'Ipv6Packet'

我的理解是，python路径尚可，并且python模块正在从pacp到以太网，ipv6到ipv4的整个链中运行。然后，ipv4尝试再次加载ipv6，脚本崩溃了。

我认为代码正在触发导入循环。

有人知道我在做什么错吗？