def __get_client_address(self, environ):
        try:
            return environ['HTTP_X_FORWARDED_FOR'].split(',')[-1].strip()
        except KeyError:
            return environ['REMOTE_ADDR']
Finds all the objects in the specified container that are not present
dataset/ETHPy150Open galaxyproject/pulsar/pulsar/web/framework.py/Controller.__get_client_address--crossover with--dataset/ETHPy150Open rackspace/pyrax/pyrax/object_storage.py/StorageClient._delete_objects_not_in_list