在单词列表上实现合并排序-将原始单词追加回列表？

def merge_sort(word_list):
    if len(word_list) <= 1:
        return word_list
    
    mid = len(word_list) // 2
    left_list = word_list[:mid]
    right_list = word_list[mid:]
    
    left_list = merge_sort(left_list)
    right_list = merge_sort(right_list)
    
    return merge(left_list, right_list)

def merge(left_list, right_list):
    merged_list = []
    i = j = 0
    
    while i < len(left_list) and j < len(right_list):
        if left_list[i] < right_list[j]:
            merged_list.append(left_list[i])
            i += 1
        else:
            merged_list.append(right_list[j])
            j += 1
    
    while i < len(left_list):
        merged_list.append(left_list[i])
        i += 1
    
    while j < len(right_list):
        merged_list.append(right_list[j])
        j += 1
    
    return merged_list

def append_original_words(word_list, original_words):
    return word_list + original_words

# 测试代码
words = ['apple', 'banana', 'cherry', 'date']
original_words = ['elderberry', 'fig']

sorted_words = merge_sort(words)
result = append_original_words(sorted_words, original_words)

print(result)