class TemTest:

    def __init__(self,):

        self.x=[i for i in range(10)]

    def __len__(self):

        return len(self.x)

    def __getitem__(self, item):

        return self.x[item]

    def __setitem__(self, key, value):

        self.x[key]=value

    def __delitem__(self, key):

        del self.x[key]

    def __contains__(self, item):

        return item in self.x

    def __repr__(self):

        return '{}'.format(self.x)

test=TemTest() #实例化

print(len(test)) #返回长度

print(test[0])   #打印下标0的值

print(test[:3])  #切片

test[3]=10       #将下标3的值替换为10

print(test)

del test[3]      #删除下标3的值

print(test)

print(1 in test)  #测试in运算符

print(3 in test)  

10

0

[0, 1, 2]

[0, 1, 2, 10, 4, 5, 6, 7, 8, 9]

[0, 1, 2, 4, 5, 6, 7, 8, 9]

True

False