I python novice, when flipping through python.org/dev/peps/pep-0484/-sharpthe-type-of-class-objects" rel=" nofollow noreferrer "> pep484 , and mypy , I encountered something I didn"t understand, as follows:

-sharp Construct an empty Stack[int] instance
stack = Stack[int]()
stack.push(2)
stack.pop()
stack.push("x") -sharp Type error

my personal understanding is:

• T indicates any type
• Stack [int] means Stack can only store int types, so if a string is passed below, an error can be reported
.

doubts are:

• I don"t know if the above understanding is correct
.
• if I had identified the data types in the heap in the first place, why would I create a generic type?
• does generics have any usage scenarios in python ? I haven"t come into contact with languages such as java , so I think it"s very abstract to look at the examples, and I don"t know how to use them in the above scenarios.

I have just come into contact with python . Please forgive me if there are any misunderstandings. I hope my seniors will be able to solve the doubts.