from compiler.ast import flatten

python3删除了flatten包

但可用一下代码段代替

import collections

def flatten(x):

result = []

for elin x:

if isinstance(x, collections.Iterable)and not isinstance(el,str):

result.extend(flatten(el))

else:

result.append(el)

return result

print(flatten(["junk", ["nested stuff"], [], [[]]]))