[python-advocacy] help me~!!!'tuple' object has no attribute 'compile'

[yao]

my code
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# -*- coding: utf8 -*-
#!/usr/bin/python

import urllib
import urllib2
import re
import MySQLdb

conn=MySQLdb.connect
(host="localhost",user="root",passwd="ylj",db="net", charset="utf8")
cur = conn.cursor()
sql='select
net_site.downline_re,net_site.down_re,net_cha.id,net_cha.urlid,net_cha.source_url

from net_site,net_cha where net_site.id=net_cha.urlid'
cur.execute(sql)
re=cur.fetchall()
if len(re)!=0:
for i in re:
down_re="%s"%(i[1])
source_url="%s"%(i[4])
data= urllib2.urlopen(source_url).read()
res=re.compile(down, re_DOTALL).findall(data)
print str
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when it's run,the eric give error
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The debugged program raised the exception unhandled AttributeError
"'tuple' object has no attribute 'compile'"
File: /var/www/py/down.py, Line: 27
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the line:27 -------> res=re.compile(down, re_DOTALL).findall(data)