text: from flask import Flask
  from sqlalchemy import create_engine
  from sqlalchemy.orm import scoped_session, sessionmaker
  #from sqlalchemy.ext.declarative import declarative_base
  
  app = Flask(__name__)
  app.config.from_pyfile('config.py')
  
  engine = create_engine(app.config['DB_URL'], encoding='utf-8')
  db_session = scoped_session(sessionmaker(autocommit=False,
                                           autoflush=False,
                                           bind=engine))