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Python

Posted by YiChen Chen
YiChen Chen
5,228 Points

I don't understand why this can invert key and value of dictionary

Dic1 =  {'aa': 0,  'bb': 1,  'cc': 2,  'dd': 3,  'ee': 4}
Dic2 = {} 
for k,v in Dic.items():
    Dic2[v]=k

Dic2 = {0: 'aa', 1: 'bb', 2: 'cc', 3: 'dd', 4: 'ee'}

I don't know what it means Dic2[v]=k

1 Answer

Andreas cormack
.a{fill-rule:evenodd;}techdegree seal-36
Andreas cormack
Python Web Development Techdegree Graduate 33,011 Points

Hi YiChen

# first there is a typo i think it should be Dic1.items() and not Dic.items

for k,v in Dic1.items():  # k stands for key and v stands for value
    Dic2[v]= k # this line makes the value of Dic1 the key of Dic2 and key of Dic1 the value of Dic2

hope this helps