raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
HTTPError: HTTP Error 403: Forbidden

headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 6.3; Win64; x64; rv:55.0) Gecko/20100101 Firefox/55.0'}
request = url_req.Request(url, headers=headers)
response = url_req.urlopen(request, data=None, timeout=3)
html = response.read().decode('GBK')

# -*- coding: utf-8 -*-
"""
Created on Fri Aug 11 16:31:42 2017
@author: lart
"""

import urllib.request as url_req
import re, socket, time


def r_o_html(url):
  print('r_o_html begin')

  headers = {'User-Agent': 'Mozilla/5.0 (Windows NT 6.3; Win64; x64; rv:55.0) Gecko/20100101 Firefox/55.0'}

  request = url_req.Request(url, headers=headers)

  NET_STATUS = False
  while not NET_STATUS:
    try:
      response = url_req.urlopen(request, data=None, timeout=3)
      html = response.read().decode('GBK')
      print('NET_STATUS is good')
      print('r_o_html end')
      return html
    except socket.timeout:
      print('NET_STATUS is not good')
      NET_STATUS = False

def re_findall(re_string, operation, html):

  print('re_findall begin')
  pattern = re.compile(re_string, re.I)

  if operation == 'findall':
    result = pattern.findall(html)
  else:
    print('this operation is invalid')
    exit(-1)

  print('re_findall end')
  return result


if __name__ == '__main__':
  url_base = 'http://www.7kankan.la/book/1/'

  html = r_o_html(url_base)

  findall_title = re_findall(r'<title>(.+?)</title>', 'findall', html)

  findall_chapter = re_findall(r'<dd class="col-md-3"><a href=[\',"](.+?)[\',"] title=[\',"](.+?)[\',"]>', 'findall', html)

  with open(findall_title[0] + '.txt', 'w+', encoding='utf-8') as open_file:
    print('article文件打开', findall_chapter)
    for i in range(len(findall_chapter)):
      print('第' + str(i) + '章')

      open_file.write('\n\n\t' + findall_chapter[i][1] + '\n --------------------------------------------------------------------- \n')

      url_chapter = url_base + findall_chapter[i][0]

      html_chapter = r_o_html(url_chapter)

      findall_article = re_findall(r'    (.+?)<br />', 'findall', html_chapter)

      findall_article_next = findall_chapter[i][0].replace('.html', '_2.html')

      url_nextchapter = url_base + findall_article_next

      html_nextchapter = r_o_html(url_nextchapter)

      if html_nextchapter:
        findall_article.extend(re_findall(r'    (.+?)<br />', 'findall', html_nextchapter))

        for text in findall_article:
          open_file.write(text + '\n')

      time.sleep(1)

  print('文件写入完毕')