async def adelete(self, key: str, collection: str = DEFAULT_COLLECTION) -> bool:
        """
        Delete a value from the store.

        Args:
            key (str): key
            collection (str): collection name

        """
        from sqlalchemy import delete

        self._initialize()
        async with self._async_session() as session:
            async with session.begin():
                result = await session.execute(
                    delete(self._table_class)
                    .filter_by(namespace=collection)
                    .filter_by(key=key)
                )
        return result.rowcount > 0

        Delete a value from the store.

        Args:
            key (str): key
            collection (str): collection name

        
llama-index-integrations/storage/kvstore/llama-index-storage-kvstore-postgres/llama_index/storage/kvstore/postgres/base.py