python - Python 遍历字典：TypeError: unpack non-sequence

Question

sub = {} 
for a, b in sub:                   #<--- error occurs here
   for s in b:
       #do blah. I was told a b is a list

它给了我TypeError: unpack non-sequence

这是什么意思？

Answer 1

你在找这个吗？

for a, b in sub.iteritems():
    # Do Something.

正在做

for a, b in sub:
    #...

尝试分配(a, b)给sub可能不是序列的键。