def _get_existing_indexes(self) -> List[MarqoIndex]:
        """
        Get all Marqo indexes storing in _MARQO_SETTINGS_SCHEMA_NAME schema (used prior to Marqo v2.13.0).
        This method is now only used to retrieve the existing indexes for bootstrapping from v2.13.0

        Returns:
            List of Marqo indexes
        """
        batch_response = self.vespa_client.get_all_documents(self._MARQO_SETTINGS_SCHEMA_NAME, stream=True)
        if batch_response.continuation:
            # TODO - Verify expected behaviour when streaming. Do we need to expect and handle pagination?
            raise InternalError("Unexpected continuation token received")

        return [
            MarqoIndex.parse_raw(document.fields['settings'])
            for document in batch_response.documents
            if not document.id.split('::')[-1].startswith(constants.MARQO_RESERVED_PREFIX)
        ]

        Get all Marqo indexes storing in _MARQO_SETTINGS_SCHEMA_NAME schema (used prior to Marqo v2.13.0).
        This method is now only used to retrieve the existing indexes for bootstrapping from v2.13.0

        Returns:
            List of Marqo indexes
        
src/marqo/core/index_management/index_management.py