如何在文本文件中包含带有模式的字符串的行尾添加文本？

import re

def add_text_to_file(file_path, pattern, text_to_add):
    with open(file_path, 'r') as file:
        lines = file.readlines()

    with open(file_path, 'w') as file:
        for line in lines:
            if re.search(pattern, line):
                line = line.rstrip('\n') + text_to_add + '\n'
            file.write(line)

# 示例用法
file_path = 'example.txt'  # 替换为目标文本文件的路径
pattern = 'pattern'  # 替换为目标模式的字符串
text_to_add = 'text to add'  # 替换为需要添加的文本

add_text_to_file(file_path, pattern, text_to_add)