python 字典 pop

字典也有pop
pop(key[,default])

a = {1:2,3:4,5:6}
b = a.pop(3,None)
a

输出:

{1: 2, 5: 6}

没有key

a = {1:2,3:4,5:6}
b = a.pop(7,None)
a

输出:

{1: 2, 3: 4, 5: 6}