Chainbreaker2 hashing issue

[bidea117]

When I try to extract my WiFi passwords I get the follow error, any ideas on how to fix it?

sh-3.2# python3 chainbreaker.py -k -o /Users/me/Downloads/keychain-export/ --export-all /Library/Keychains/System.keychain --unlock-file /private/var/db/SystemKey
Unlock Key:
Traceback (most recent call last):
File "/Users/me/chainbreaker/chainbreaker.py", line 1256, in
keychain_md5 = hashlib.md5(args.keychain).hexdigest()
^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: Strings must be encoded before hashing

I used the hexdump command to gey the key but does not seem to work "hexdump -s 8 -n 24 -e '1/1 "%.2x"' /path/to/SystemKey && echo"