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 trapped_signals(cls, new_signal_handler):
        """A contextmanager which temporarily overrides signal handling.

        NB: This method calls signal.signal(), which will crash if not called from the main thread!
        """
        previous_signal_handler = cls.reset_signal_handler(new_signal_handler)
        try:
            yield
        finally:
            cls.reset_signal_handler(previous_signal_handler)