old_contents: import os
  
  CSRF_ENABLED = True
  SECRET_KEY = 'you-will-never-guess'
  # heroku addons:add heroku-postgresql:dev
  # heroku pg:promote HEROKU_POSTGRESQL_{COLOR}_URL
  SQLALCHEMY_DATABASE_URI = 'postgresql://saul:saul@localhost/test'
  # os.environ.get('DATABASE_URL')
  
new_contents: import os
  
  CSRF_ENABLED = True
  SECRET_KEY = 'you-will-never-guess'
  # heroku addons:add heroku-postgresql:dev
  # heroku pg:promote HEROKU_POSTGRESQL_{COLOR}_URL
  SQLALCHEMY_DATABASE_URI = os.environ.get('DATABASE_URL')
  
subject: fix SQLALCHEMY_DATABASE_URI