In this part, the immutable object(不可变对象) is important. That means the object cann’t be modify in any time. Only can change the direction of object.
information = {‘yuhanyu’:7,’guilin’:6,’man’:3}
print(information[‘yuhanyu’])
information[‘man’] = 4
print(information[‘man’])
information.pop(‘man’)
print(information)
num = set([5,6,7])
print(num)
num2 = set([5,5,6,6,7,7])
print(num2)
num2.add(8)
print(num2)
num2.remove(5)
print(num2)
print(num & num2)
print(num | num2)