langchain/chains/llm_summarization_checker/base.py/LLMSummarizationCheckerChain/_call
class LLMSummarizationCheckerChain:    def _call(
        self,
        inputs: Dict[str, Any],
        run_manager: Optional[CallbackManagerForChainRun] = None,
    ) -> Dict[str, str]:
        _run_manager = run_manager or CallbackManagerForChainRun.get_noop_manager()
        all_true = False
        count = 0
        output = None
        original_input = inputs[self.input_key]
        chain_input = original_input
        while not all_true and count < self.max_checks:
            output = self.sequential_chain(
                {"summary": chain_input}, callbacks=_run_manager.get_child()
            )
            count += 1

            if output["all_true"].strip() == "True":
                break

            if self.verbose:
                print(output["revised_summary"])

            chain_input = output["revised_summary"]

        if not output:
            raise ValueError("No output from chain")

        return {self.output_key: output["revised_summary"].strip()}