Django Error in SeaFile CE 6.3.4

Seems 6.3.4 changed some django and now It got and Internal Server Error caused by a deletion of all folders in seafile-server-latest. After repairing seafile-server-latest I father get this error In the logs:
ViewDoesNotExist: Could not import 'django.views.defaults.page_not_found'. Parent module django.views.defaults does not exist.
Any solutions for that or can that message be ignored?

Now also got this:
‘2018-09-25 13:41:38,298 [WARNING] _reject Forbidden (Referer checking failed - no Referer.): /’

I watchted the log another days and someone tried to open phpmyadmin, which I haven’t installed. Seems like some automated hacker attacks.