这似乎是一个已知的错误： https://bugs.launchpad.net/django-openid-auth/+bug/1252826

This seems to be a known bug: https://bugs.launchpad.net/django-openid-auth/+bug/1252826

但是，截至目前，似乎没有修复。

However, as of now, there doesn't seem to be a fix.

解决方法，根据此评论，是重置序列化程序：

SESSION_SERIALIZER ='django.contrib.sessions.serializers.PickleSerializer'