小册名称：Python合辑7-集合、列表与元组
什么是集合？
my_set = {10, 20, 30, 10, 20, 20, 20}print(my_set, type(my_set))
my_set = {10, 20, 30, 10, 20, 20, 20}
print(my_set, type(my_set))
