'Verify signal does not update expiration for verified mode with explicitly set expiration.'

@ddt.data(1, 14, 30)
def test_verified_mode_explicitly_set(self, verification_window):

    (course_mode, __) = self.create_mode('verified', 'verified', 10)
    course_mode.expiration_datetime_is_explicit = True
    self.assertIsNone(course_mode.expiration_datetime)
    with patch('course_modes.models.CourseModeExpirationConfig.current') as config:
        instance = config.return_value
        instance.verification_window = timedelta(days=verification_window)
        _listen_for_course_publish('store', self.course.id)
        course_mode.refresh_from_db()
        self.assertEqual(course_mode.expiration_datetime, (self.end - timedelta(days=verification_window)))
