python:按字典中的特定键和这些键值的总和分组

这是一种使用简单迭代的方法。

前任:

from collections import defaultdict
dict_ot={"Berlin":4, "London":3,"Madrid":3,"Germany":51, "Others":1, "France":4}
grpBy = [("Germany", "Berlin"), ("Madrid", "Others"), ("London",)]
res = defaultdict(int)
for i in grpBy:
    for j in i:
        res[i] += dict_ot[j]

for k, v in res.items():
    print("{}: {}".format(", ".join(k), v))

输出:

Germany, Berlin: 55
London: 3
Madrid, Others: 4