def METHOD_NAME(self, migrate_db_for):
    import ckan.model as model
    has_table = model.Session.bind.has_table
    assert not has_table("example_database_migrations_x")
    assert not has_table("example_database_migrations_y")
    migrate_db_for("example_database_migrations")
    assert has_table("example_database_migrations_x")
    assert has_table("example_database_migrations_y")