use six to support python 2 and 3

ox/web/google.py

@@ -1,7 +1,7 @@
 # -*- coding: utf-8 -*-
 # vi:si:et:sw=4:sts=4:ts=4
 import re
-import urllib
+from six.moves import urllib
 
 import ox
 from ox import strip_tags, decode_html
@@ -13,9 +13,9 @@ def read_url(url, data=None, headers=ox.net.DEFAULT_HEADERS, timeout=DEFAULT_TIM
     return ox.cache.read_url(url, data, headers, timeout, unicode=True)
 
 def quote_plus(s):
-    if not isinstance(s, str):
+    if not isinstance(s, bytes):
         s = s.encode('utf-8')
-    return urllib.quote_plus(s)
+    return urllib.parse.quote_plus(s)
 
 def find(query, max_results=DEFAULT_MAX_RESULTS, timeout=DEFAULT_TIMEOUT):
     """