How to use the stepfunctions.StepFunctions function in stepfunctions

thread = PropagatingThread(target=worker_thread, args=(
                account_id,
                sts,
                config,
                s3,
                cache,
                kms_dict
            ))
            thread.start()
            threads.append(thread)

        for thread in threads:
            thread.join()

        LOGGER.info("Executing Step Function on Deployment Account")
        step_functions = StepFunctions(
            role=deployment_account_role,
            deployment_account_id=deployment_account_id,
            deployment_account_region=config.deployment_account_region,
            regions=config.target_regions,
            account_ids=account_ids,
            update_pipelines_only=0
        )

        step_functions.execute_statemachine()
    except ParameterNotFoundError:
        LOGGER.info(
            'You are now ready to bootstrap a deployment account '
            'by moving it into your deployment OU. '
            'Once you have moved it into the deployment OU, '
            'be sure to check out its progress in AWS Step Functions'
        )

def lambda_handler(event, _):
    sts = STS()

    role = sts.assume_cross_account_role(
        'arn:aws:iam::{0}:role/{1}'.format(
            event['deployment_account_id'],
            event['cross_account_access_role']),
        'step_function')

    step_functions = StepFunctions(
        role=role,
        deployment_account_id=event['deployment_account_id'],
        deployment_account_region=event['deployment_account_region'],
        full_path=event['full_path'],
        regions=event['regions'],
        account_ids=[event['account_id']],
        update_pipelines_only=1 if event.get('moved_to_protected') or event.get('moved_to_root') else 0,
        error=event.get('error', 0)
    )
    step_functions.execute_statemachine()

    return event