There's a discussion on the Python dev mailing list about removing asyncore and asynchat from Python 3.11:
https://mail.python.org/archives/list/python-dev@python.org/thread/LZOOLX5EKOITW55TW7JQYKLXJUPCAJB4/#LVFBHVNV3INGKVVRONVRIA3Q6JIYXMZM
pyftpdlib would need to be migrated to asyncio (#310) or ship with a copy of asyncore and asynchat to continue to work if these modules are removed from the stdlib.