App Engine blank page whenever new code is added

[Pazarito via StackOverflow]

So I just downloaded Google App Engine and was going through the Google's tutorial, all was working fine but suddenly I started getting blank pages. Now the only code that displays in the browser is the default one and the built-in guestbook example.

import webapp2

class MainHandler(webapp2.RequestHandler):
    def get(self):
        self.response.out.write('Hello world!')

app = webapp2.WSGIApplication([
    ('/', MainHandler)
], debug=True)

This works. But if I add just one line to the existing code...

def get(self):
    self.response.headers['Content-Type'] = 'text/plain' #!!!!!!!
    self.response.write('Hello, World!')

Nothing gets displayed.

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http://stackoverflow.com/questions/23275724/app-engine-blank-page-whenever-new-code-is-added

[Pazarito via StackOverflow]

So I just downloaded Google App Engine and was going through the Google's tutorial, all was working fine but suddenly I started getting blank pages. Now the only code that displays in the browser is the default one and the built-in guestbook example.

import webapp2

class MainHandler(webapp2.RequestHandler):
    def get(self):
        self.response.out.write('Hello world!')

app = webapp2.WSGIApplication([
    ('/', MainHandler)
], debug=True)

This works. But if I add just one line to the existing code...

def get(self):
    self.response.headers['Content-Type'] = 'text/plain' #!!!!!!!
    self.response.write('Hello, World!')

Nothing gets displayed.

*UPDATE

Checked the App Engine log, this is what it says.