def fibonacci(n: int) -> ListNode: Return a the head of a linked list representing the Fibonacci Sequence up to the given number of n places. Each integer in this sequence is the sum of the previous two integers (except for the first two integers, 0 and 1, which are base values not derived from adding other integers). Assume n is non-negative; if it is zero, return an empty list. >>> fibonacci(5) ListNode(0, ListNode(1, ListNode(1, ListNode(2, ListNode(3, None) >>>> def zip_lists(xs: Optional[ListNode), ys: Optional[ListNode]) -> Optional[ListNode]: Return the head of a linked list that represents the pair-wise combination of the given linked lists. If one list runs out of ListNodes, append the remainder of the other list. >>> XS = ListNode(1, ListNode (2, ListNode(3, None))) >>> ys = ListNode(4, None) >>> zip_lists(xs, ys) ListNode(1, ListNode(4, ListNode(2, ListNode(3, None)))) def unzip_list(head: Optional[ListNode] ) -> Tuple[Optional[ListNode), Optional[listNode]]: Return a 2-tuple of heads of linked lists that represents the pair-wise separation of the given linked lists. This operation is the inverse of zip_lists. >>> head = ListNode(1, ListNode(4, ListNode(2, \ ListNode(5, ListNode(3, None))))) >>> unzip_list(head) (ListNode(1, ListNode (2, ListNode(3, None))), \ ListNode(4, ListNode(5, None)))