code: func (runtime *DockerRuntime) PullImage(image string) error {
  	out, err := runtime.exec.Command("docker", "pull", image).CombinedOutput()
  	if err != nil {
  		return errors.Wrapf(err, "output: %s, error", string(out))
  	}
  	return nil
  }
docs: // PullImage pulls the image