如何在python中找到元素之和最高的嵌套列表中的子集？

def find_max_subset(nested_list):
    max_sum = float('-inf')
    max_subset = []

    def dfs(subset, total_sum):
        nonlocal max_sum, max_subset

        if total_sum > max_sum:
            max_sum = total_sum
            max_subset = subset

        for sublist in subset:
            if isinstance(sublist, list):
                dfs(sublist, total_sum + sum(sublist))

    dfs(nested_list, sum(nested_list))
    return max_subset

# 示例调用
nested_list = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
result = find_max_subset(nested_list)
print("最高和的子集：", result)
print("子集元素之和：", sum(result))