如何获取换行符<br>前后的字符串

def get_strings_around_newline(input_string):
    newline_chars = ["\r\n", "\n", "\r"]
    for newline_char in newline_chars:
        if newline_char in input_string:
            parts = input_string.split(newline_char)
            if len(parts) > 1:
                return parts[0], parts[1]
    return None, None

# 示例用法
input_string = "Hello\nWorld"
before_newline, after_newline = get_strings_around_newline(input_string)
print("Before newline:", before_newline)
print("After newline:", after_newline)