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