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Reviewed in https://codereview.appspot.com/14351043/

bkeyvani/appengine-guestbook-python,Romzz/appengine-guestbook-python,wcyuan/weather-mailer,t9nf/appengine-guestbook-python,jerarl/gcp-appengine-python,adjohnson916/appengine-guestbook-python,jeffgodwyll/appengine-flask-guestbook,jeffgodwyll/appengine-flask-guestbook,ashwini0529/appengine-guestbook-python,t9nf/appengine-guestbook-python,JonGal/appengine-ml-demo,dmolson/appengine-guestbook-python,JackConnor/portfolio,adjohnson916/appengine-guestbook-python,dmolson/appengine-guestbook-python,GoogleCloudPlatform/appengine-guestbook-python,ashwini0529/appengine-guestbook-python,JonGal/appengine-ml-demo,JackConnor/portfolio,artificechicago/camp2016,bkeyvani/appengine-guestbook-python,wcyuan/weather-mailer,GoogleCloudPlatform/appengine-guestbook-python,thejeshgn/appengine-guestbook-python,thejeshgn/appengine-guestbook-python,artificechicago/camp2016,jerarl/gcp-appengine-python,Romzz/appengine-guestbook-python