class test:
    def __setitem__(self,key,value):
        print('setitem')
        self.__dict__[key]=value
    def __getitem__(self,item):
        print('getitem')
        return self.__dict__[item]
    def __delitem__(self,key):
        print('delitem')
        self.__dict__.pop(key)
f=test()
f['name']='dengtou'
f['height']=18
print(f.__dict__)
del f['name']
print(f.__dict__)
print(f['height'])