Incus import OCI container image error: Backup is missing at "backup/index.yaml"

1

since incus support running OCI containers, does incus import command support importing OCI images that are exported using docker save imagename > image.tar command ?

when I am trying to import an OCI image, I got following error:

danny@home:~$ incus import upsonic_gca_docker_ubuntu.tar
Importing instance: 100% (887.47MB/s)Error: Backup is missing at "backup/index.yaml"
2

No, incus import is for importing backups made with incus export.