langchain/experimental/plan_and_execute/agent_executor.py/PlanAndExecute/_call
class PlanAndExecute:    def _call(
        self,
        inputs: Dict[str, Any],
        run_manager: Optional[CallbackManagerForChainRun] = None,
    ) -> Dict[str, Any]:
        plan = self.planner.plan(
            inputs,
            callbacks=run_manager.get_child() if run_manager else None,
        )
        if run_manager:
            run_manager.on_text(str(plan), verbose=self.verbose)
        for step in plan.steps:
            _new_inputs = {"previous_steps": self.step_container, "current_step": step}
            new_inputs = {**_new_inputs, **inputs}
            response = self.executor.step(
                new_inputs,
                callbacks=run_manager.get_child() if run_manager else None,
            )
            if run_manager:
                run_manager.on_text(
                    f"*****\n\nStep: {step.value}", verbose=self.verbose
                )
                run_manager.on_text(
                    f"\n\nResponse: {response.response}", verbose=self.verbose
                )
            self.step_container.add_step(step, response)
        return {self.output_key: self.step_container.get_final_response()}