old_contents: from .base import *
  
  import dj_database_url
  
  DEBUG = False
  
  db_from_envronment = dj_database_url.config()
  DATABASES = {
      'default': db_from_envronment
  }
  
new_contents: from .base import *
  
  import dj_database_url
  
  DEBUG = False
  
  ALLOWED_HOSTS = ['.herokuapp.com']
  
  db_from_envronment = dj_database_url.config()
  DATABASES = {
      'default': db_from_envronment
  }
  
subject: add herokuapp domain to allowed hosts in production