[Python] Need help finding deadloop in this linked list python code! (Leetcode 328)

I'm trying to solve Leetcode Q328:

Given the head of a singly linked list, group all the nodes with odd indices together followed by the nodes with even indices, and return the reordered list.

Here is my code:

# Definition for singly-linked list.
# class ListNode:
# def __init__(self, val=0, next=None):
# self.val = val
# self.next = next
class Solution:
def oddEvenList(self, head: Optional[ListNode]) -> Optional[ListNode]:
node = head
odd = True
lastOdd = None
while node:
temp = node.next
if node.next:
if node.next.next:
node.next = node.next.next
else:
if odd:
lastOdd = node
else:
if odd:
lastOdd = node
break
node = temp
odd = not(odd)
lastOdd.next = head.next
return head


When tested with [1,2,3,4,5], I would either run out of time or memory, so I'm assuming there is a deadloop somewhere. But I've combed through the logic a couple of times and couldn't find it!

I'm relatively sure that the deadloop happens with the following part as deleting this part will allow the program to finish:

else:
if odd:
lastOdd = node


This is actually already the second version of my code, originally it was:

else:
if odd:
node.next = head.next


But why does it deadloop? I have used temp to store the next node in the original chain separately already, and the loop should just stop after node reaches the end of the chain!

Any help is appreciated! I'm just starting to learn about linked lists so it might be a really dumb question.

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