+cookiejar = cookielib.CookieJar()
+urlopener = urllib2.build_opener(urllib2.HTTPCookieProcessor(cookiejar))
+def _urlopen(url, referrer=None):
+ req = urllib2.Request(url)
+ req.add_header("User-Agent", USER_AGENT)
+ if referrer:
+ req.add_header("Referer", referrer)
+ return urlopener.open(req)