Plan to support BitcoinCash? · Issue #171 · petertodd/python-bitcoinlib · GitHub

It looks like some updates are needed:
bitcoin/core/script.py line 930 need to be removed for BitCoinCash. Also, SIGHASH_FORKID and FORKID should be defined as well.

Source : https://github.com/petertodd/python-bitcoinlib/issues/171#issuecomment-383858234