python 迭代多个对象

并行迭代　　zip

for a,b,c in zip(list,list,tuple,list):

　　print a,b,c

串行迭代　　itertools.chain

a = [1,2,3,4,5]

b = [2,3,4,5,6]

for x in chain(a,b):

　　print x