'Custom _clone with privacy level propagation.'

def _clone(self, *args, **kwargs):

    if (kwargs.get('klass', None) == ValuesQuerySet):
        kwargs['klass'] = UserProfileValuesQuerySet
    c = super(UserProfileQuerySet, self)._clone(*args, **kwargs)
    c._privacy_level = getattr(self, '_privacy_level', None)
    return c
