爬虫爬到的text正常输出，但写入文件时是空的

import requests
from lxml import etree
import json
# for i in range(1, 4):
#     res = requests.get(f'https://www.51shucheng.net/kehuan/santi/santi{i}')
#     res.encoding = 'utf-8'
#     html = etree.HTML(res.text)
#     titles = html.xpath('/html/body/div/div[3]/div[2]/div[6]/ul//li/a/@title')
#     hrefs = html.xpath('/html/body/div/div[3]/div[2]/div[6]/ul//li/a/@href')
#     for href in hrefs:
#         smalltitle = titles[hrefs.index(href)]
#         print(smalltitle, href)
#         response = requests.get(href)
#         response.encoding = 'utf-8'
#         html = etree.HTML(response.text)
#         text = html.xpath('//*[@id="neirong"]//text()')
#         text2 = ''.join(text).replace('(adsbygoogle = window.adsbygoogle || []).push({});','')
#         with open(f'三体/{smalltitle}.txt', 'w',encoding='utf-8')  as file:
#             file.write(text2)

res = requests.get(f'https://www.51shucheng.net/sidamingzhu/hongloumeng')
res.encoding = 'utf-8'
html = etree.HTML(res.text)
titles = html.xpath('/html/body/div/div[3]/div[2]/div[5]/ul//li/a/@title')
hrefs = html.xpath('/html/body/div/div[3]/div[2]/div[5]/ul//li/a/@href')
for href in hrefs:
    smalltitle = titles[hrefs.index(href)]
    print(smalltitle, href)
    response = requests.get(href)
    response.encoding = 'utf-8'
    html = etree.HTML(response.text)
    text = html.xpath('//*[@id="neirong"]//text()')
    text2=''.join(text)
    with open(f'红楼梦/{smalltitle}.txt', 'w',encoding='utf-8') as file:
        file.write(text2)

注释掉的内容爬取的是网站的另一本小说，完全没有问题

下面的是爬取红楼梦

写入文件并没有报错但打开是这个样子

问题出在with open(f'红楼梦/{smalltitle}.txt', 'w',encoding='utf-8') as file:这行，文件名中含":",不符合系统对文件名的命名规则，导致无法写入文件。改成with open(f'红楼梦/{smalltitle.split(":")[0]}.txt', 'w', encoding='utf-8') as f:即可。