# !/usr/bin/env python3
# -*- coding: utf-8 -*-


# 练习
class Student(object):
    count = 0
    def __init__(self, name):
        self.name = name
        Student.count += 1

# 测试

if Student.count != 0:
    print('测试失败！')
else:
    bart = Student('Bart')
    if Student.count != 1:
        print('测试失败！')
    else:
        lisa = Student('Lisa')
        if Student.count != 2:
            print('测试失败！')
        else:
            print('Students:', Student.count)
            print('测试成功！')
            
