patch 8.2.3423: Vim9: list += list creates a new list in :def function Commit: https://github.com/vim/vim/commit/07802044b90b2cbcc64b2dfe235f019d7c37589c Author: Bram Moolenaar <Bram@vim.org> Date: Thu Sep 9 23:01:14 2021 +0200 patch 8.2.3423: Vim9: list += list creates a new list in :def function Problem: Vim9: list += list creates a new list in :def function. Solution: Append to the existing list.

#!/usr/bin/env python
#
# Server that will accept connections from a Vim channel.
# Used by test_channel.vim.
#
# This requires Python 2.6 or later.

from test_channel import main, ThreadedTCPServer
import socket

class ThreadedTCP6Server(ThreadedTCPServer):
    address_family = socket.AF_INET6

if __name__ == "__main__":
    main("::", 0, ThreadedTCP6Server)