对组使用python正则表达式替换，以获取被替换的字符

import re

def replace_and_get_replaced(text, pattern, replacement):
    # 使用re.sub()函数进行替换，并将替换后的结果和被替换的字符一起返回
    def replace(match):
        replaced_text = match.group(0)
        return replacement

    replaced_text = re.sub(pattern, replace, text)
    return replaced_text

text = "Hello, my name is John Doe. I am 25 years old."
pattern = r"\b\w+\b"  # 匹配单词
replacement = "****"

replaced_text = replace_and_get_replaced(text, pattern, replacement)
print("Replaced text:", replaced_text)