Сортировка слиянием

def merge_sort(unsorted_list):
  if len(unsorted_list) == 1:
    return unsorted_list
  mid = len(unsorted_list) // 2
  left = merge_sort(unsorted_list[: mid])
  right = merge_sort(unsorted_list[mid :])
  return merge_sort_two(left, right)
 
def merge_sort_two(left, right):
  output_list = []
  i = j = 0
  while i < len(left) and j < len(right):
    if left[i] < right[j]:
      output_list.append(left[i])
      i += 1
    else:
      output_list.append(right[j])
      j += 1
  if i < len(left):
    output_list.append(left[i:])
  if j < len(right):
    output_list.append(right[j:])
  return output_list

TypeError                                 Traceback (most recent call last)
 
<ipython-input-38-924c11ab5dbd> in <module>()
----> 1 merge_sort([6, 42, 15, 0, 4])
 
2 frames
 
<ipython-input-36-1d42e7dd7fd7> in merge_sort_two(left, right)
     11   i = j = 0
     12   while i < len(left) and j < len(right):
---> 13     if left[i] < right[j]:
     14       output_list.append(left[i])
     15       i += 1
 
TypeError: '<' not supported between instances of 'int' and 'list'

def merge_sort2(unsorted_list):
  if len(unsorted_list) == 1:
    return unsorted_list
  mid = len(unsorted_list) // 2
  left = merge_sort2(unsorted_list[: mid])
  right = merge_sort2(unsorted_list[mid :])
  return left, right

merge_sort2([6, 42, 15, 0, 4])
(([6], [42]), ([15], ([0], [4])))

    # дозаписываем остаток
    if i < len(left):
        out.extend(left[i:])
       
    # дозаписываем остаток
    if j < len(right):
        out.extend(right[j:])

# дозаписываем остаток
    while i < len(left):
        out.append(left[i])
        i += 1
    # дозаписываем остаток
    while j < len(right):
        out.append(right[j])
        j += 1