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

        messages = list(response.context['messages'])
        self.assertEqual(
            messages[0].message,
            'You specified a non-integer election ID.'
        )
        self.assertRedirects(response, reverse('results'))
def _file_name_to_batch_number(example_file_name):
    """Parses batch number from file.

    :param example_file_name: See doc for `find_example_file`.
    :return: batch_number: Integer.
    :raises: ValueError: if batch number cannot be parsed from file name.
    """

    pathless_file_name = os.path.split(example_file_name)[-1]
    extensionless_file_name = os.path.splitext(pathless_file_name)[0]
    return int(extensionless_file_name.split('input_examples_batch')[-1])