def METHOD_NAME(parallel_execution_handler_fn_arn: str):
    # GIVEN
    payload = json.dumps({"message": "Powertools for AWS Lambda (Python) - Parallel execution"})
    invocation_options = [
        GetLambdaResponseOptions(lambda_arn=parallel_execution_handler_fn_arn, payload=payload, raise_on_error=False),
        GetLambdaResponseOptions(lambda_arn=parallel_execution_handler_fn_arn, payload=payload, raise_on_error=False),
    ]
    # WHEN executing Lambdas in parallel
    execution_result_list = get_lambda_response_in_parallel(invocation_options)
    timeout_execution_response = execution_result_list[0][0]["Payload"].read().decode("utf-8")
    error_idempotency_execution_response = execution_result_list[1][0]["Payload"].read().decode("utf-8")
    # THEN
    assert "Execution already in progress with idempotency key" in error_idempotency_execution_response
    assert "Task timed out after" in timeout_execution_response