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POWhat is going on with this code from the Google App Engine tutorial
 

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  1. POWhat is going on with this code from the Google App Engine tutorial
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    <pre><code>import cgi from google.appengine.api import users from google.appengine.ext import webapp from google.appengine.ext.webapp.util import run_wsgi_app from google.appengine.ext import db class Greeting(db.Model): author = db.UserProperty() content = db.StringProperty(multiline=True) date = db.DateTimeProperty(auto_now_add=True) class MainPage(webapp.RequestHandler): def get(self): self.response.out.write('&lt;html&gt;&lt;body&gt;') greetings = db.GqlQuery("SELECT * FROM Greeting ORDER BY date DESC LIMIT 10") for greeting in greetings: if greeting.author: self.response.out.write('&lt;b&gt;%s&lt;/b&gt; wrote:' % greeting.author.nickname()) else: self.response.out.write('An anonymous person wrote:') self.response.out.write('&lt;blockquote&gt;%s&lt;/blockquote&gt;' % cgi.escape(greeting.content)) # Write the submission form and the footer of the page self.response.out.write(""" &lt;form action="/sign" method="post"&gt; &lt;div&gt;&lt;textarea name="content" rows="3" cols="60"&gt;&lt;/textarea&gt;&lt;/div&gt; &lt;div&gt;&lt;input type="submit" value="Sign Guestbook"&gt;&lt;/div&gt; &lt;/form&gt; &lt;/body&gt; &lt;/html&gt;""") class Guestbook(webapp.RequestHandler): def post(self): greeting = Greeting() if users.get_current_user(): greeting.author = users.get_current_user() greeting.content = self.request.get('content') greeting.put() self.redirect('/') application = webapp.WSGIApplication( [('/', MainPage), ('/sign', Guestbook)], debug=True) def main(): run_wsgi_app(application) if __name__ == "__main__": main() </code></pre> <p>I am new to Python and a bit confused looking at this Google App Engine tutorial code. In the Greeting class, content = db.StringProperty(multiline=True), but in the Guestbook class, "content" in the greeting object is then set to greeting.content = self.request.get('content').</p> <p>I don't understand how the "content" variable is being set in the Greeting class as well as the Guestbook class, yet seemingly hold the value and properties of both statements.</p>
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