old_contents: from flask import Flask
  app = Flask(__name__)
  
  @app.route("/")
  def hello():
     print "test"
     return "Hello World"
  
  if __name__ == "__main__":
     app.run(host='0.0.0.0', debug=True, port=80)
  
new_contents: from flask import Flask
  app = Flask(__name__)
  
  @app.route("/")
  def hello():
     print "test"
     return "Hello World from Flask"
  
  if __name__ == "__main__":
     app.run(host='0.0.0.0', debug=True, port=80)
  
subject: Update example-flask