需要帮助将函数应用于python中的列表列表

original_list = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]

# 将每个子列表中的元素平方
new_list = [[x**2 for x in sublist] for sublist in original_list]

print(new_list)

[[1, 4, 9], [16, 25, 36], [49, 64, 81]]

original_list = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
new_list = []

for sublist in original_list:
    new_sublist = []
    for item in sublist:
        new_sublist.append(item**2)
    new_list.append(new_sublist)

print(new_list)

[[1, 4, 9], [16, 25, 36], [49, 64, 81]]