python chained creational OOP design pattern problem

class Validator:
    _not_validated_config: NotValidatedConfig

    def __init__(self, not_validated_config: NotValidatedConfig):
        self._not_validated_config = not_validated_config

    def validate_config(self) -> ValidatedConfig:
        return (
            Phase4Validation(
                Phase3Validation(
                    Phase2Validation(
                        Phase1Validation(
                            self._not_validated_config
                        ).validate()
                    ).validate()
                ).validate()
            ).validate()
        )

    # Alternative
    def validate_config2(self) -> ValidatedConfig:
        validated_phase1_config: ValidatedPhase1Config = Phase1Validation(self._not_validated_config).validate()
        validated_phase2_config: ValidatedPhase2Config = Phase2Validation(validated_phase1_config).validate()
        validated_phase3_config: ValidatedPhase3Config = Phase3Validation(validated_phase2_config).validate()
        validated_phase4_config: ValidatedPhase4Config = Phase4Validation(validated_phase3_config).validate()
        return validated_phase4_config