input: Write a python function to merge two lists and remove duplicates.
  assert merge_list(["apple","orange","banana"], ["cherry","pineapple","apple"]) == ["apple", "orange", "banana", "cherry", "pineapple"]
  assert merge_list([1, 2, 3], [3, 4, 5]) == [1, 2, 3, 4, 5]
  assert merge_list(["a", "b", "c"], ["b", "c", "d"]) == ["a", "b", "c", "d"]
  assert merge_list([], ["a", "b", "c"]) == ["a", "b", "c"]
  assert merge_list([1, 2, 3], []) == [1, 2, 3]
output: def merge_list(list1, list2):
      return list(dict.fromkeys(list1 + list2))