pyhton3 zip() ;sys.stdout;

1、zip()

>>> a =[one,two,three]

>>> b=[1,2,3]

>>> zipped=zip(a,b)

>>> print(zipped)

<zip object at 0x10396f588>

In python 3, zip() returns an iterable object, so the above example returns an object, not a specific value.

>>> c = zip(a,b)

>>> for value in c:

...     print(value)

... 

('one', 1)

('two', 2)

('three', 3)

In python2, return the value directly

>>> zipped=zip(a,b)

>>> print(zipped)

... 

('one', 1)

('two', 2)

('three', 3)

2、sys.stdout

import  sys
f_result=open('result.txt', 'w')
sys.stdout=f_result                 # print to text

3. The difference between python2 and python3 to judge whether the dictionary has a certain key

‘’‘python2’‘’
def cmpjson(x, y):
    if x.has_key('name'):
        return x['name'] > y['name']


'''python3'''
def cmpjson(x, y):
    if x.__contains__('name'):
        return x['name'] > y['name']