实现了Mysql短线重连而不是为确保安全每次写mysql都要连接一次。
用递归的方式实现Mysql连接函数失败时自动重连，失败次数太大时发出提示。
尽在不言中，贴之

import bs4
import MySQLdb
from bs4 import BeautifulSoup
import time
import sys
import datetime

__OUT__ = sys.stdout

#try to connect mysql, it will alert you when connect fail more than five times 
def _connect_mysql(deep):
    if deep > 5:
        __out__ = sys.stdout
        sys.stdout = __OUT__
        print 'Maybe mysql server can not work'
        sys.stdout = __out__
        time.sleep(10)
    try:
        conn = MySQLdb.connect(host='',user='',passwd='',db='',port=)
    except:
        time.sleep(0.5)
        return _connect_mysql(deep+1)
    else:
        return conn

#try to write infoomation to mysql, it will return True if it write success,else return False
def _write_mysql(con, _problem_id, _title, _description, _input, _output, _sample_input, _sample_output, _author, _recommend, _info_temp):
    try:
        cur = con.cursor()
        cur.execute('set names utf8')
    except:
        return False
    else:
        sql = ('INSERT INTO `hdu_problem`'
                '(`problem_id`, `title`, `description`, `input`, `output`, `sample_input`,'
                ' `sample_output`, `author`, `recommend`, `info_temp`, `get_time`)'
                ' VALUES (%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)',
                    (_problem_id, _title.encode('utf-8'), _description.encode('utf-8'),
                     _input.encode('utf-8'), _output.encode('utf-8'), _sample_input.encode('utf-8'),
                     _sample_output.encode('utf-8'), _author.encode('utf-8'), _recommend.encode('utf-8'),
                     _info_temp.encode('utf-8'), datetime.datetime.now()))
        cur.execute(*sql)
        con.commit()
        return True

number = 1000
con = _connect_mysql(0)
while True:
    print number
    content = open(str(number) + '.html')
    soup = BeautifulSoup(content, 'html.parser')
    _title = soup.h1.text
    if _title == 'System Message':
        print _title
    else:
        _info_temp = soup.find_all(style='font-family:Arial;font-size:12px;font-weight:bold;color:green')[0].text
        content = soup.find_all(class_='panel_title')
        for i in content:
            item = i.find_next_sibling()
            if i.text == 'Problem Description':
                del(item['class'])
                img = item.find_all('img')
                if img!=[]:
                    for one_img in img:
                        if one_img.attrs['src'][0] == '.':
                            img_url_head = 'http://acm.hdu.edu.cn/'
                        else:
                            img_url_head = 'http://acm.hdu.edu.cn'
                        one_img.attrs['src'] = img_url_head + one_img.attrs['src']
                _description = item
            elif i.text == 'Input':
                del(item['class'])
                _input= item
            elif i.text == 'Output':
                del(item['class'])
                _output= item
            elif i.text == 'Sample Input':
                del(item['class'])
                _sample_input= item
            elif i.text == 'Sample Output':
                del(item['class'])
                _sample_output= item
            elif i.text == 'Author':
                del(item['class'])
                _author= item
            elif i.text == 'Recommend':
                del(item['class'])
                _recommend= item
    flag = False
    _times = 1
    while True:
        print 'I will write to mysql, try' , _times
        if _write_mysql(con, number, _title, _description, _input, _output, _sample_input, _sample_output, _author, _recommend, _info_temp):
            print 'write success'
            break
        else:
            #reconnect tomysql when lost connection
            _times += 1
            con = _connect_mysql(0) 
    number += 1