code: func (scaler *JobPsuedoScaler) ScaleSimple(namespace, name string, preconditions *ScalePrecondition, newSize uint) (string, error) {
  	job, err := scaler.JobsClient.Jobs(namespace).Get(name, metav1.GetOptions{})
  	if err != nil {
  		return "", err
  	}
  	if preconditions != nil {
  		if err := validateJob(job, preconditions); err != nil {
  			return "", err
  		}
  	}
  	parallelism := int32(newSize)
  	job.Spec.Parallelism = &parallelism
  	updatedJob, err := scaler.JobsClient.Jobs(namespace).Update(job)
  	if err != nil {
  		return "", err
  	}
  	return updatedJob.ObjectMeta.ResourceVersion, nil
  }
docs: // ScaleSimple is responsible for updating job's parallelism. It returns the
  // resourceVersion of the job if the update is successful.