程序源代码：
#!/usr/bin/python
# -*- coding: UTF-8 -*-
if __name__ == '__main__':
class student:
x = 0
c = 0
def f(stu):
stu.x = 20
stu.c = 'c'
a= student()
a.x = 3
a.c = 'a'
f(a)
print a.x,a.c以上实例输出结果为：
20 c
