python---assert用法

# -*- coding: utf -8 -*-

from socket import gethostname, gethostbyname
from exceptions import AssertionError

def get_local_ip():
    '''
       Return local host ip. 
    '''
    ip = gethostbyname(gethostname())
    assert ip != '127.0.1.1', 'No network connect, please the network connect again!'   # 不应该是怎样的，就写成怎样
    return ip


try:
    print get_local_ip()
except AssertionError,  e:
    print e

$ python get_localhost_ip.py
No network connect, please the network connect again!