I was using the latest stable version 0.6.0 updated to using python3.
When attempting to connect to Atlassian Crowd version 4.0 an error would appear in the syslog: “getting bytes expecting str” and the user would never be authenticated using Crowd.
Finally traced this down to an issue where urllib.readlines() is returning bytes, but the auth_crowd.py module was expecting a string.
Enclosed is a patch file for one way to fix this. It should work for python2 but I have not tried fix this under python2. I also suspect this has nothing to do with the version of Crowd.