Python CodeLab字典遍历

Question

问题是这就是我目前所拥有的：

dict(nafta_capitals) = canadian_capitals, mexican_capitals, us_capitals

给定三个与变量canadian_capital、mexican_capital和us_capital相关联的字典，将各省或州映射到各自的首都，创建一个将这三个字典组合在一起的新字典，并将其与变量nafta_Papital相关联。

Answer 1

您可能需要使用defaultdict-这里nafta被用作以下三个（canadian_capitals, mexican_capitals, us_capitals）的密钥-

>>>dic = defaultdict(list)
>>>lst = ['nafta1', 'canadian_capitals1', 'mexican_capitals1', 'us_capitals1', 'nafta2', 'canadian_capitals2', 'mexican_capitals2', 'us_capitals2']
>>>grouped_lst = [lst[i:i+4] for i in range(0,len(lst),4)]
>>>[['nafta1', 'canadian_capitals1', 'mexican_capitals1', 'us_capitals1'], ['nafta2', 'canadian_capitals2', 'mexican_capitals2', 'us_capitals2']]
>>>for i in grouped_lst:dic[i[0]]=i[1:]
>>>dic.items()
>>>[('nafta1', ['canadian_capitals1', 'mexican_capitals1', 'us_capitals1']), ('nafta2', ['canadian_capitals2', 'mexican_capitals2', 'us_capitals2'])]
>>>for i in dic.keys():print dic[i]
>>>['canadian_capitals1', 'mexican_capitals1', 'us_capitals1']
['canadian_capitals2', 'mexican_capitals2', 'us_capitals2']