Copy a list

Question

I want to copy a list to work only with that copy. But if I do so: list1 = list2, every change in list2 is also in list1. Is this something like reference? What is a short way to do this by value. To get two different lists?
https://code.sololearn.com/c0fg7sBjI8H9/?ref=app

Answer 1

If the 2 list are named as list1 and list2 and you want to copy list1 to list2 then
list1=list(list2)
Is the answer to your questions

Answer 2

If it's a simple list that doesn't contain other lists, you can just use either

list1 = list2[:]

or

list1 = list(list2)

Both create separate copies of the list.

If the list contain sub-lists, you need to make copies of these as well, which is uncomplicated if you know comprehensions:

list1 = [li[:] for li in list2]

For more complicated cases there is a module copy with deepcopy function in it.