import heapq
combined = list(dict.fromkeys(heapq.merge(list1, list2)))
**Answer 2**
def combine(l1, l2):
for i in reversed(range(min(map(len, (l1, l2))))):
if l1[i] == l2[i]:
return l1[:end := i + 1] + list(heapq.merge(l1[end:], l2[end:]))
**Answer 3**
combined = sorted(list1 + list(set(list2).difference(list1)))
**Answer 4**
from itertools import chain
combined = sorted(chain(list1, set(list2).difference(list1)))