Set all marked submissions to "grading finished".
            This is intended to support grading corrections on a larger scale.

def setGradingFinishedStateAction(self, request, queryset):
        '''
            Set all marked submissions to "grading finished".
            This is intended to support grading corrections on a larger scale.
        '''
        for subm in queryset:
            subm.state = Submission.GRADED
            subm.save()