import urllib2, ssl
context = ssl._create_unverified_context()
urllist = ['https://www.pochta.ru', 
    'http://lectureswww.readthedocs.org/',
    'http://9gag.com',
    'http://ya.ru']
handler = urllib2.HTTPSHandler(context=context)
for url in urllist:
    request = urllib2.Request(url)
    request.add_header('User-Agent', 'Mozilla 5.10')
    opener = urllib2.build_opener(handler)
    response = opener.open(request)
    if response.headers.get('Last-Modified'):
    	print " ".join([url, response.headers.get('Last-Modified')])

roman@roman-Satellite-A300:~/Documents/python/py$ python check.py 
http://lectureswww.readthedocs.org/ Thu, 29 Oct 2015 16:10:13 GMT
http://ya.ru Thu, 17 Dec 2015 14:20:37 GMT