def METHOD_NAME(
    nullable_type_test_data,
    nullable_type_target,
    downcast_util,
    data_type,
):
    if data_type == "X":
        data = nullable_type_test_data()
    else:
        data = nullable_type_target(ltype="IntegerNullable")
    data_d = downcast_util(
        data,
        handle_boolean_nullable=False,
        handle_integer_nullable=False,
    )
    assert data_d is data