docs: def image_absent(name):
      '''
      Ensure image is absent on the computenode
  
      name : string
          uuid of image
  
      .. note::
  
          computenode.image_absent will only remove the image if it is not used
          by a vm.
      '''
      ret = {'name': name,
             'changes': {},
             'result': None,
             'comment': ''}
  
      uuid = None
      if _is_uuid(name):
          uuid = name
      if _is_docker_uuid(name):
          uuid = __salt__['imgadm.docker_to_uuid'](name)
  
      if not uuid or uuid not in __salt__['imgadm.list']():
          # image not imported
          ret['result'] = True
          ret['comment'] = 'image {0} is absent'.format(name)
      else:
          # check if image in use by vm
          if uuid in __salt__['vmadm.list'](order='image_uuid'):
              ret['result'] = False
              ret['comment'] = 'image {0} currently in use by a vm'.format(name)
          else:
              # delete image
              if __opts__['test']:
                  ret['result'] = True
              else:
                  image = __salt__['imgadm.get'](uuid)
                  image_count = 0
                  if image['manifest']['name'] == 'docker-layer':
                      # NOTE: docker images are made of multiple layers, loop over them
                      while image:
                          image_count += 1
                          __salt__['imgadm.delete'](image['manifest']['uuid'])
                          if 'origin' in image['manifest']:
                              image = __salt__['imgadm.get'](image['manifest']['origin'])
                          else:
                              image = None
                  else:
                      # NOTE: normal images can just be delete
                      __salt__['imgadm.delete'](uuid)
  
              ret['result'] = uuid not in __salt__['imgadm.list']()
              if image_count:
                  ret['comment'] = 'image {0} and {1} children deleted'.format(name, image_count)
              else:
                  ret['comment'] = 'image {0} deleted'.format(name)
              ret['changes'][name] = None
  
      return ret