How to use the devilry.apps.core.models.AssignmentGroup.objects.filter function in devilry

def _get_assignmentgroup_queryset(self):
        return AssignmentGroup.objects.filter(parentnode=self.assignment)

def __get_last_feedbackset_ids_from_posted_group_ids(self, form):
        """
        Get IDs of the last ``FeedbackSet``s on the groups that was posted.
        Args:
            form: form with group data.

        Returns:
            (list): of the posted groups last ``FeedbackSet`` IDs.
        """
        group_ids = self.__get_selected_group_ids(form=form)
        feedback_set_ids = core_models.AssignmentGroup.objects\
            .filter(id__in=group_ids)\
            .values_list('cached_data__last_feedbackset_id', flat=True)
        return list(feedback_set_ids)

def get_queryset_for_role(self, role):
        return AssignmentGroup.objects.filter(parentnode=role).select_related('parentnode')

def get_queryset(self, assignment, relatedexaminer):
        queryset = coremodels.AssignmentGroup.objects \
            .filter(parentnode_id=assignment.id) \
            .filter_user_is_examiner(user=relatedexaminer.user)
        return queryset

def __failed_from_group_queryset(self):
        """
        Get all `AssignmentGroup`s that failed the selected earlier assignment.
        """
        return AssignmentGroup.objects\
            .filter(parentnode_id=self.from_assignment.id)\
            .filter(cached_data__last_feedbackset__grading_published_datetime__isnull=False)\
            .filter(cached_data__last_feedbackset__grading_points__lt=self.from_assignment.passing_grade_min_points)

Lower(Concat('relatedstudent__user__fullname',
                             'relatedstudent__user__shortname')))
        examinerqueryset = Examiner.objects\
            .select_related('relatedexaminer__user')\
            .only(
                'relatedexaminer',
                'assignmentgroup',
                'relatedexaminer__automatic_anonymous_id',
                'relatedexaminer__user__shortname',
                'relatedexaminer__active',
                'relatedexaminer__user__fullname',
            )\
            .order_by(
                Lower(Concat('relatedexaminer__user__fullname',
                             'relatedexaminer__user__shortname')))
        queryset = coremodels.AssignmentGroup.objects\
            .filter(parentnode=self.assignment)\
            .prefetch_related(
                models.Prefetch('candidates',
                                queryset=candidatequeryset))\
            .prefetch_related(
                models.Prefetch('examiners',
                                queryset=examinerqueryset))\
            .annotate_with_is_waiting_for_feedback_count()\
            .annotate_with_is_waiting_for_deliveries_count()\
            .annotate_with_is_corrected_count() \
            .annotate_with_number_of_private_groupcomments_from_user(user=self.request.user) \
            .annotate_with_number_of_private_imageannotationcomments_from_user(user=self.request.user)\
            .distinct() \
            .select_related('cached_data__last_published_feedbackset',
                            'cached_data__last_feedbackset',
                            'cached_data__first_feedbackset',

def _get_groups(self, assignmentid):
        """
        Get a list of group dictionaries.
        """
        fields = ('id', 'name', 'is_open', 'feedback__grade', 'feedback__points',
                  'feedback__is_passing_grade', 'feedback__save_timestamp',
                  'num_deliveries')
        qry = AssignmentGroup.objects.filter(parentnode=assignmentid)
        qry = qry.select_related('feedback')
        qry = qry.annotate(num_deliveries=Count('deadlines__deliveries'))
        return qry.values(*fields)

def get_extra_preview_data(self, period):
        assignment_count = Assignment.objects.filter(parentnode=period).count()
        assignment_group_count = AssignmentGroup.objects.filter(parentnode__parentnode=period).count()
        group_comments = GroupComment.objects.filter(feedback_set__group__parentnode__parentnode=period)
        comment_file_count = CommentFile.objects\
            .filter(comment_id__in=group_comments.values_list('id', flat=True)).count()
        return '\t\t- Assignments: {}' \
               '\n\t\t- Assignment groups: {}' \
               '\n\t\t- Comments: {}' \
               '\n\t\t- Files: {}'.format(
            assignment_count,
            assignment_group_count,
            group_comments.count(),
            comment_file_count
        )

def get_assignment_groups_without_any_examiners(self):
        return AssignmentGroup.objects.filter(parentnode=self.request.cradmin_role, examiners__isnull=True)