sudo docker run --rm --volumes-from fiisoftjupyterlab_jupyterlab_1 -v $(pwd):/backup busybox tar cvf backup.tar /opt/app/data

--rm: remove the container when it exits
--volumes-from DATA: attach to the volumes shared by the DATA container
-v $(pwd):/backup: bind mount the current directory into the container; to write the tar file to
busybox: a small simpler image - good for quick maintenance
tar cvf /backup/backup.tar /data: creates an uncompressed tar file of all the files in the /data directory