I upgraded recently to Django 1.8. In previous versions of Django, the following import was fine:
from django.contrib.contenttypes.management import update_
It seems django team has removed the update_contenttypes function without a mention in the release notes because isn't a documented, public API. (as the said here: https://code.djangoproject.com/ticket/28092)
Now you can use instead the new function create_contenttypes, as you can see here: https://github.com/django/django/commit/6a2af01452966d10155b720f4f5e7b09c7e3e419