Useable? Yes
Stable? No. If you want more stable version and have Python 2 installed, use last pywallet update on 2014 (https://github.com/jackjack-jj/pywallet/tree/b52c955f8c93a75745166ebf281448016e1f22e2).
Python 3 supported? Yes, but @jackjack never mentioned if all pywallet functional support Python 3.