'Synchronization behavior is predictable'

def test_migrate_selection(self):

    self.assertTrue(router.allow_migrate_model('default', User))
    self.assertTrue(router.allow_migrate_model('default', Book))
    self.assertTrue(router.allow_migrate_model('other', User))
    self.assertTrue(router.allow_migrate_model('other', Book))
    with override_settings(DATABASE_ROUTERS=[TestRouter(), AuthRouter()]):
        self.assertTrue(router.allow_migrate_model('default', User))
        self.assertTrue(router.allow_migrate_model('default', Book))
        self.assertTrue(router.allow_migrate_model('other', User))
        self.assertTrue(router.allow_migrate_model('other', Book))
    with override_settings(DATABASE_ROUTERS=[AuthRouter(), TestRouter()]):
        self.assertFalse(router.allow_migrate_model('default', User))
        self.assertTrue(router.allow_migrate_model('default', Book))
        self.assertTrue(router.allow_migrate_model('other', User))
        self.assertTrue(router.allow_migrate_model('other', Book))
