old_contents: from os import environ
  import yaml
  
  from edx_course_discovery.settings.base import *
  from edx_course_discovery.settings.utils import get_env_setting
  
  
  DEBUG = False
  TEMPLATE_DEBUG = DEBUG
  
  ALLOWED_HOSTS = ['*']
  
  LOGGING = environ.get('LOGGING', LOGGING)
  
  CONFIG_FILE = get_env_setting('COURSE_DISCOVERY_CFG')
  with open(CONFIG_FILE) as f:
      config_from_yaml = yaml.load(f)
      vars().update(config_from_yaml)
  
  DB_OVERRIDES = dict(
      PASSWORD=environ.get('DB_MIGRATION_PASS', DATABASES['default']['PASSWORD']),
      ENGINE=environ.get('DB_MIGRATION_ENGINE', DATABASES['default']['ENGINE']),
      USER=environ.get('DB_MIGRATION_USER', DATABASES['default']['USER']),
      NAME=environ.get('DB_MIGRATION_NAME', DATABASES['default']['NAME']),
      HOST=environ.get('DB_MIGRATION_HOST', DATABASES['default']['HOST']),
      PORT=environ.get('DB_MIGRATION_PORT', DATABASES['default']['PORT']),
  )
  
  for override, value in DB_OVERRIDES.iteritems():
      DATABASES['default'][override] = value
  
new_contents: from os import environ
  import yaml
  
  from edx_course_discovery.settings.base import *
  from edx_course_discovery.settings.utils import get_env_setting
  
  
  DEBUG = False
  TEMPLATE_DEBUG = DEBUG
  
  ALLOWED_HOSTS = ['*']
  
  LOGGING = environ.get('LOGGING', LOGGING)
  
  CONFIG_FILE = get_env_setting('COURSE_DISCOVERY_CFG')
  with open(CONFIG_FILE) as f:
      config_from_yaml = yaml.load(f)
      vars().update(config_from_yaml)
  
  DB_OVERRIDES = dict(
      PASSWORD=environ.get('DB_MIGRATION_PASS', DATABASES['default']['PASSWORD']),
      ENGINE=environ.get('DB_MIGRATION_ENGINE', DATABASES['default']['ENGINE']),
      USER=environ.get('DB_MIGRATION_USER', DATABASES['default']['USER']),
      NAME=environ.get('DB_MIGRATION_NAME', DATABASES['default']['NAME']),
      HOST=environ.get('DB_MIGRATION_HOST', DATABASES['default']['HOST']),
      PORT=environ.get('DB_MIGRATION_PORT', DATABASES['default']['PORT']),
  )
  
  for override, value in DB_OVERRIDES.items():
      DATABASES['default'][override] = value
  
subject: Use python3 dictionary iteration