def caculate(ITEMS, need, i): #i，need为int型ITEMS为一个二维的元组
temp1 = list(ITEMS)
temp1[i] = list(temp1[i])
temp1[i][INDEX_ITEM_TOTAL_QAUNTITY] = list(temp1[i][INDEX_ITEM_TOTAL_QAUNTITY])
temp1[i][INDEX_ITEM_TOTAL_QAUNTITY] = temp1[i][INDEX_ITEM_TOTAL_QAUNTITY]-need
temp1[i][INDEX_ITEM_TOTAL_QAUNTITY] = tuple(temp1[i][INDEX_ITEM_TOTAL_QAUNTITY])
ITEMS[i] = tuple(temp1[i])
ITEMS = tuple(temp1)
运行结果如下：
temp1[i][INDEX_ITEM_TOTAL_QAUNTITY] = list(temp1[i][INDEX_ITEM_TOTAL_QAUNTITY])
TypeError: 'int' object is not iterable
问题出在i上吗，我该如何进行更改呢？
或者，该代码的目的是进行数量的加减，如何在元组情况下更改其中某项元素（例如库存数量的增减）？
元组如下：
ITEMS = (("MacBook Pro", "Apple", 2), ("AC1200 Wireless Adapter", "ALFA Network", 4), ("Jetson Nano Developer Kit", "NVIDIA", 3), ("WRT1900AC Dual-Band Wi-Fi Router", "Linksys", 2), ("RoboMaster EP", "DJI", 2))
ITEMS = (("MacBook Pro", "Apple", 2), ("AC1200 Wireless Adapter", "ALFA Network", 4), ("Jetson Nano Developer Kit", "NVIDIA", 3), ("WRT1900AC Dual-Band Wi-Fi Router", "Linksys", 2), ("RoboMaster EP", "DJI", 2))
list(ITEMS）是这样的：
[('MacBook Pro', 'Apple', 2), ('AC1200 Wireless Adapter', 'ALFA Network', 4), ('Jetson Nano Developer Kit', 'NVIDIA', 3), ('WRT1900AC Dual-Band Wi-Fi Router', 'Linksys', 2), ('RoboMaster EP', 'DJI', 2)]
建议你讲ITEMS定义成字典或将temp1[i]再用list转一次才能修改
temp1[i][INDEX_ITEM_TOTAL_QAUNTITY] = list(temp1[i][INDEX_ITEM_TOTAL_QAUNTITY]) 这一行有错
temp1[i][INDEX_ITEM_TOTAL_QAUNTITY] 是int，不能使用list
而且list只能转一层，也就是temp1[i]还是一个元组，不能这样赋值
转list的目的是什么？ int型数据不能转的