python - defaultdict 如何获取列表中所有值的总和？

Question

代码如下:

models = [Url1, Url2, Url3, Url4, Url5, Url6, Url7, Url8, Url9, Url10]
d = defaultdict(list)

for model in models:

    getids = model.objects.values_list('keyword', 'score')
    for kw, score in getids:
        d[kw].append(score)

这使得'd'输出这个:

defaultdict(<type 'list'>, {198: [-70, 0, 5, -70, 5, 5, 0, 0, -50, -70],     
199: [0, -70, -70, -70, -70, -70, -100, -70, -70, -70]})

如何让它返回:

defaultdict({198: -245, 199: -660}) #sum of all numbers inside lists, returned as values to both keys.

我尝试了循环，但 deafultdict 似乎不像普通列表那样工作。

Answer 1

试试这个:

d = defaultdict(int)

for model in models:

    getids = model.objects.values_list('keyword', 'score')
    for kw, score in getids:
        d[kw] += score