def set_index_id(self, index_id: str) -> None:
        """
        Set the index id.

        NOTE: if you decide to set the index_id on the index_struct manually,
        you will need to explicitly call `add_index_struct` on the `index_store`
        to update the index store.

        Args:
            index_id (str): Index id to set.

        """
        # delete the old index struct
        old_id = self._index_struct.index_id
        self._storage_context.index_store.delete_index_struct(old_id)
        # add the new index struct
        self._index_struct.index_id = index_id
        self._storage_context.index_store.add_index_struct(self._index_struct)

        Set the index id.

        NOTE: if you decide to set the index_id on the index_struct manually,
        you will need to explicitly call `add_index_struct` on the `index_store`
        to update the index store.

        Args:
            index_id (str): Index id to set.

        
llama-index-core/llama_index/core/indices/base.py