ID of unassigned list value

Question

I see in python that ID of unassigned list value is always the same. For example id([1]) and id([1,2]) is same. How does it define this value and where I can read about such behavior?

Answer 1

It doesn't matter if you assign a list somewhere or not.

As soon as you write a list literal, the list will be created.

That means, Python will take memory for that and give an id.

The only difference is that the object will be garbage-collected after the statement is over, if you don't put a reference to it.

So list is created...

... destroyed...

... and the now free id is given to the new list.

At least that's what I'd suspect.

Try this:

print(id([]))
# a = []
print(id([]))

Id is the same.

Now if you uncomment line 2, the id differs.

Answer 2

Its a ways down there but there's a lot of good information here on the whole
https://towardsdatascience.com/JUMP_LINK__&&__python__&&__JUMP_LINK-variable-assignment-9f43aed91bff