Python删除非字母字符，但有例外

import re

def remove_non_alpha_except_exceptions(text, exceptions):
    # 构建一个正则表达式，匹配所有非字母和非例外字符
    pattern = f"[^a-zA-Z{''.join(exceptions)}]"
    # 使用re.sub函数替换匹配到的字符为空字符串
    cleaned_text = re.sub(pattern, '', text)
    return cleaned_text

# 示例使用
text = "Hello, World! This is a test. 123 #Python."
exceptions = "#."  # 保留的例外字符
cleaned_text = remove_non_alpha_except_exceptions(text, exceptions)
print(cleaned_text)  # 输出: HelloWorldThisisatest.#Python

text = "Hello.World.This.is.a.test."
exceptions = "."
pattern = f"[^a-zA-Z\\{exceptions}]"
cleaned_text = re.sub(pattern, '', text)
print(cleaned_text)  # 输出: HelloWorldThisisatest.