async def _aget_retrieved_ids_and_texts(
        self, query: str, mode: RetrievalEvalMode = RetrievalEvalMode.TEXT
    ) -> Tuple[List[str], List[str]]:
        """Get retrieved ids and texts, potentially applying a post-processor."""
        retrieved_nodes = await self.retriever.aretrieve(query)

        if self.node_postprocessors:
            for node_postprocessor in self.node_postprocessors:
                retrieved_nodes = node_postprocessor.postprocess_nodes(
                    retrieved_nodes, query_str=query
                )

        return (
            [node.node.node_id for node in retrieved_nodes],
            [node.text for node in retrieved_nodes],
        )
Get retrieved ids and texts, potentially applying a post-processor.
llama-index-core/llama_index/core/evaluation/retrieval/evaluator.py