如何修改代码在file文件以及sentences文件中高亮匹配的关键词（以<b></b>形式）表示？

import re
with open('keyword.txt', 'r') as file:
    keyword = [word.strip() for word in file.readlines()]
with open('file.txt', 'r') as file:
    article = file.read()
unmatched_keywords = []
matched_sentences = []
for word in keyword:
    pattern = re.compile(fr'\b{re.escape(word)}\b')
    match = re.search(pattern, article)
    if match:
        sentence_pattern = r'[^.!?]*' + re.escape(word) + r'[^.!?]*[.!?]'
        sentences = re.findall(sentence_pattern, article)
        matched_sentence = next((s for s in sentences if word in s), None)
        if matched_sentence:
            article = article.replace(matched_sentence, f"<b>{matched_sentence}<b>", 1)
            matched_sentences.append(matched_sentence)
        else:
            unmatched_keywords.append(word)
    else:
        unmatched_keywords.append(word)
with open("new.txt", "w") as file:
    file.write(article)
with open('unmatched_keywords.txt', 'w') as file:
    for word in unmatched_keywords:
        file.write(word + '\n')
with open("sentences.txt", "w") as file:
    file.write('\n'.join(matched_sentences))

一段代码，要求keyword匹配file，同时生成三个文件，一个文件是修改以后的file，一个是未匹配的关键字unmatchd，还有一个是提取关键字所在的句子
sentences（keyword只匹配一次），
如何修改代码在file文件以及sentences文件中高亮匹配的关键词（以形式）表示？

以下回答引用了gpt生成，请参考是否解决了问题：
要修改代码以便在文件和句子中以 <b></b> 形式突出显示匹配的关键词，您需要对替换逻辑进行调整。请使用以下修改后的代码：

import re

with open('keyword.txt', 'r') as file:
    keywords = [word.strip() for word in file.readlines()]

with open('file.txt', 'r') as file:
    article = file.read()

unmatched_keywords = []
matched_sentences = []

for keyword in keywords:
    pattern = re.compile(fr'\b{re.escape(keyword)}\b')
    match = re.search(pattern, article)

    if match:
        sentence_pattern = r'[^.!?]*' + re.escape(keyword) + r'[^.!?]*[.!?]'
        sentences = re.findall(sentence_pattern, article)
        matched_sentence = next((s for s in sentences if keyword in s), None)

        if matched_sentence:
            article = article.replace(matched_sentence, f"<b>{matched_sentence}</b>", 1)
            matched_sentences.append(matched_sentence)
        else:
            unmatched_keywords.append(keyword)
    else:
        unmatched_keywords.append(keyword)

with open("new.txt", "w") as file:
    file.write(article)

with open("unmatched_keywords.txt", "w") as file:
    for keyword in unmatched_keywords:
        file.write(keyword + '\n')

with open("sentences.txt", "w") as file:
    file.write('\n'.join(matched_sentences))

以上代码将会在 file.txt 文件中将匹配到的关键词用 <b> 和 </b> 标签包裹起来，表示为高亮。同时，匹配到的句子将会被保存在 sentences.txt 文件中。