old_contents: from  flask import Flask
  
  app = Flask(__name__)
  
  
  @app.route("/")
  def home():
      return "<h1>Demosntrando para Galera</h1>"
  
  if __name__ == '__main__':
      app.run()
  
new_contents: from  flask import Flask
  
  app = Flask(__name__)
  
  
  @app.route("/")
  def home():
      return "<h1>Testando...</h1>"
  
  if __name__ == '__main__':
      app.run()
  
subject: Update message