docs: def extract_name_from_job_arn(arn):
      """Returns the name used in the API given a full ARN for a training job
      or hyperparameter tuning job.
      """
      slash_pos = arn.find('/')
      if slash_pos == -1:
          raise ValueError("Cannot parse invalid ARN: %s" % arn)
      return arn[(slash_pos + 1):]