code: async function ensureAwsCfStack(cli, params) {
    if (await awsCfStackExists(cli, params.StackName)) {
      await updateAwsCfStack(cli, params);
    } else {
      await createAwsCfStack(cli, params);
    }
    const output = await awsDescribeCfStack(cli, params.StackName);
    return output;
  }
docs: update / create and return its info: