code: func (c *ContainerServer) ContainerUnpause(container string) (string, error) {
  	ctr, err := c.LookupContainer(container)
  	if err != nil {
  		return "", errors.Wrapf(err, "failed to find container %s", container)
  	}
  
  	cStatus := ctr.State()
  	if cStatus.Status == oci.ContainerStatePaused {
  		if err := c.runtime.UnpauseContainer(ctr); err != nil {
  			return "", errors.Wrapf(err, "failed to unpause container %s", ctr.ID())
  		}
  		c.ContainerStateToDisk(ctr)
  	} else {
  		return "", fmt.Errorf("the container %s is not paused", ctr.ID())
  	}
  
  	return ctr.ID(), nil
  }
docs: // ContainerUnpause unpauses a running container with a grace period (i.e., timeout).