Return a list of objects from the API for a container.

def start(self):
        """Return a list of objects from the API for a container."""
        LOG.info('Listing options...')
        with indicator.Spinner(**self.indicator_options):
            objects_list = self._list_contents()
            if not objects_list:
                return

        # Index items
        self._index_objects(objects_list=objects_list)
        # Create the underlying structure
        self._make_directory_structure()

        # Download everything
        LOG.debug('Download Items: %s', self.download_items)
        self._multi_processor(
            self._get,
            items=[i for i in self.download_items.values() for i in i]
        )