Python嵌套dict理解

Question

有人可以解释如何做嵌套的字典理解吗？

>> j = dict(((x+y,0) for x in 'cd') for y in 'ab')
>> {('ca', 0): ('da', 0), ('cb', 0): ('db', 0)}

我本来希望:

>> j
>> {'ca':0, 'cb':0, 'da':0, 'db':0}

谢谢!

Answer 1

dict((x+y,0) for x in 'cd' for y in 'ab')