old_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  """
  File: __init__.py
  Author: huxuan <i(at)huxuan.org>
  Description: Initial file for app.
  """
  
  from flask import Flask
  
  app = Flask(__name__)  # pylint: disable=invalid-name
  app.config.from_object('config')
  
  # commented as for file structure, should recover later.
  # from app import models
  
  
  @app.route('/')
  @app.route('/hellworld')
  def helloworld():
      """ Hello World for app. """
      return 'Hello world from {}!'.format(__name__)
  
new_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  """
  File: __init__.py
  Author: huxuan <i(at)huxuan.org>
  Description: Initial file for app.
  """
  
  from flask import Flask
  from flask.ext.sqlalchemy import SQLAlchemy
  
  app = Flask(__name__)  # pylint: disable=invalid-name
  app.config.from_object('config')
  
  # commented as for file structure, should recover later.
  # from app import models
  
  db = SQLAlchemy(app)
  
  
  @app.route('/')
  @app.route('/hellworld')
  def helloworld():
      """ Hello World for app. """
      return 'Hello world from {}!'.format(__name__)
  
subject: Create model in config file.