def set_config_defaults():
 cfg.set_defaults(cors.CORS_OPTS, allow_headers=['X-Auth-Token', 'X-Identity-Status', 'X-Roles', 'X-Service-Catalog', 'X-User-Id', 'X-Tenant-Id', 'X-OpenStack-Request-ID'], expose_headers=['X-Auth-Token', 'X-Subject-Token', 'X-Service-Token', 'X-OpenStack-Request-ID'], allow_methods=['GET', 'PUT', 'POST', 'DELETE', 'PATCH'])

def set_config_defaults ( ) : cfg . set_defaults ( cors . CORS_OPTS , allow_headers = [ 'X-Auth-Token' , 'X-Identity-Status' , 'X-Roles' , 'X-Service-Catalog' , 'X-User-Id' , 'X-Tenant-Id' , 'X-OpenStack-Request-ID' ] , expose_headers = [ 'X-Auth-Token' , 'X-Subject-Token' , 'X-Service-Token' , 'X-OpenStack-Request-ID' ] , allow_methods = [ 'GET' , 'PUT' , 'POST' , 'DELETE' , 'PATCH' ] )
this method updates all configuration default values .