从现有词典值新建词典

Question

我想知道如何执行以下操作：

firstDictionary = {"firstKey" : "A", "secondKey" : "B"}
secondDictionary = {"firstKey" : 3, "secondKey" : 47}
emptyDictionary = {}

for key, value in firstDictionary, secondDictionary:
    # emptyDictionary = some sort of append method...

所以

^{pr2}$

Answer 1

这很直接。您需要做的就是迭代其中一个字典项，并使用第一个字典中的键查找第二个字典的关联值。在

>>> firstDictionary = {"firstKey" : "A", "secondKey" : "B"}
>>> secondDictionary = {"firstKey" : 3, "secondKey" : 47}
>>> emptyDictionary = {value : secondDictionary.get(key, None) for key, value in firstDictionary.items()}
>>> print emptyDictionary
{'A': 3, 'B': 47}

如果您确定两个字典具有相同的键，则替换dict.获取用字典索引构造

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