old_contents: import configparser
  import os
  from flask import Flask
  from shopping_app.views import (IndexView, AddItemsView, CreateShoppingList, DashboardView,
                                  LoginView, Logout, RegisterView, RemoveShoppingList, ShoppingListDetail)
  
  BASEDIR = os.path.dirname(os.path.abspath(__file__))
  
  app = Flask(__name__)
  config = configparser.ConfigParser()
  config.read(BASEDIR + '/secret.ini')
  
  # app urls
  app.add_url_rule('/', view_func=IndexView.as_view('index'))
  app.add_url_rule('/dashboard', view_func=DashboardView.as_view('dashboard'))
  app.add_url_rule('/login', view_func=LoginView.as_view('login'))
  app.add_url_rule('/logout', view_func=Logout.as_view('logout'))
  app.add_url_rule('/register', view_func=RegisterView.as_view('register'))
  app.add_url_rule('/create-shopping-list', view_func=CreateShoppingList.as_view('create-shopping-list'))
  app.add_url_rule('/shopping-list-detail/', view_func=ShoppingListDetail.as_view('shopping-list-detail'))
  app.add_url_rule('/remove-shopping-list', view_func=RemoveShoppingList.as_view('remove-shopping-list'))
  
  # app conf
  app.debug = True
  app.secret_key = config['SECRET_KEY']['KEY']
  
  if __name__ == '__main__':
      app.run()
  
new_contents: import configparser
  import os
  from flask import Flask
  from shopping_app.views import (IndexView, AddItemsView, CreateShoppingList, DashboardView,
                                  LoginView, Logout, RegisterView, RemoveShoppingList, ShoppingListDetail)
  
  BASEDIR = os.path.dirname(os.path.abspath(__file__))
  
  app = Flask(__name__)
  config = configparser.ConfigParser()
  config.read(BASEDIR + '/secret.ini')
  
  # app urls
  app.add_url_rule('/', view_func=IndexView.as_view('index'))
  app.add_url_rule('/dashboard', view_func=DashboardView.as_view('dashboard'))
  app.add_url_rule('/login', view_func=LoginView.as_view('login'))
  app.add_url_rule('/logout', view_func=Logout.as_view('logout'))
  app.add_url_rule('/register', view_func=RegisterView.as_view('register'))
  app.add_url_rule('/create-shopping-list', view_func=CreateShoppingList.as_view('create-shopping-list'))
  app.add_url_rule('/shopping-list-detail/', view_func=ShoppingListDetail.as_view('shopping-list-detail'))
  app.add_url_rule('/remove-shopping-list', view_func=RemoveShoppingList.as_view('remove-shopping-list'))
  
  # app conf
  app.debug = True
  
  if __name__ == '__main__':
      app.run()
  
subject: Remove debug setting