def test_ref_get_with_invalid_election_id_non_existent_election_id(self):
        response = self.client.get(
            reverse('results-export'),
            { 'election': '69' },
            HTTP_REFERER=reverse('results'),
            follow=True
        )

        messages = list(response.context['messages'])
        self.assertEqual(
            messages[0].message,
            'You specified an ID for a non-existent election.'
        )
        self.assertRedirects(response, reverse('results'))
def deadlines_for_courses(cls, course_keys):
        """
        Retrieve verification deadlines for particular courses.

        Arguments:
            course_keys (list): List of `CourseKey`s.

        Returns:
            dict: Map of course keys to datetimes (verification deadlines)

        """
        all_deadlines = cache.get(cls.ALL_DEADLINES_CACHE_KEY)
        if all_deadlines is None:
            all_deadlines = {
                deadline.course_key: deadline.deadline
                for deadline in VerificationDeadline.objects.all()
            }
            cache.set(cls.ALL_DEADLINES_CACHE_KEY, all_deadlines)

        return {
            course_key: all_deadlines[course_key]
            for course_key in course_keys
            if course_key in all_deadlines
        }