This type of error typically occurs because the cached .pyc files are out of date for some reason. (C.f. https://www.py4u.net/discuss/17141, https://stackoverflow.com/questions/30861493/how-to-fix-python- valueerrorbad-marshal-data)
This specific issue is occurring not in python-cryptography itself, but rather in the /usr/bin/py3compile call when its trying to import debpython. In other words, something's inconsistent with your system's cached python code. It sounds like perhaps force reinstalling python3-minimal might be worth trying. ** Package changed: python-cryptography (Ubuntu) => python3-defaults (Ubuntu) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1935783 Title: package python3-cryptography 1.2.3-1ubuntu0.3 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/python3-defaults/+bug/1935783/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs