When reading, list is a reference to the original list, and list[:] shallow-copies the list. When assigning, list (re)binds the name and list[:] slice-assigns, replacing what was previously in the list. Also, don't use list as a name since it shadows the built-in.
The second, list(), is using the actual list type constructor to create a new list which has contents equal to the first list. (I didn't use it in the first example because you were overwriting that name in your code - which is a good example of why you don't want to do that!)
Caveats Linear time-complexity in list length An index call checks every element of the list in order, until it finds a match. If the list is long, and if there is no guarantee that the value will be near the beginning, this can slow down the code. This problem can only be completely avoided by using a different data structure.
How can I find the index for a given item in a list?
I'm working on a Power Automate flow that updates items in a SharePoint Online list. However, I'm facing an issue where certain columns (including Person/Group fields) are not appearing in the "Update item" action.
Power Automate – Some SharePoint List Columns Not Appearing in "Update ...
You cannot put lists in sets since lists are mutable and could change (which could affect whether they are duplicate to another list in the set). I would suggest a different approach for a list of lists, e.g. as covered in this question about removing duplicates from a list of lists.
It is a list with six elements in it. To understand slicing better, consider that list as a set of six boxes placed together. Each box has an alphabet in it. Indexing is like dealing with the contents of box. You can check contents of any box. But you can't check the contents of multiple boxes at once. You can even replace the contents of the box.
How do I read every line of a file in Python and store each line as an element in a list? I want to read the file line by line and append each line to the end of the list.
How to read a file line-by-line into a list? - Stack Overflow
(The list object must be iterable, implied by the for..in stanza.) The lesson here for new programmers is: You can’t get the number of items in a list without counting them at some point. The question becomes: when is a good time to count them?
How do I get the number of elements in a list (length of a list) in ...
I'm looking for a quick way to create a list of values in C#. In Java I frequently use the snippet below:
Quick way to create a list of values in C#? - Stack Overflow