async def _aremove_from_ref_doc_node(self, doc_id: str) -> None:
        """
        Helper function to remove node doc_id from ref_doc_collection.
        If ref_doc has no more doc_ids, delete it from the collection.
        """
        await self._kvstore.adelete(doc_id, collection=self._metadata_collection)

        Helper function to remove node doc_id from ref_doc_collection.
        If ref_doc has no more doc_ids, delete it from the collection.
        
llama-index-integrations/storage/docstore/llama-index-storage-docstore-azure/llama_index/storage/docstore/azure/base.py