https://en.wikipedia.org/wiki/Linked_list
Get an iterator for the LinkedList that returns a [position, item] tuple.
[position, item]
Add one or more items to the end of the list.
Remove the last item from the list and return it.
Remove the first item from the list and return it.
Add one or more items to the start of the list.
See
https://en.wikipedia.org/wiki/Linked_list