create docker image from docker container by commit

1. Run Docker base image like ubuntu 

[node1] (local) root@192.168.0.23 ~
$ docker run -it ubuntu bash
root@153c1eb1d2c4:/# apt-get update 
Get:1 http://security.ubuntu.com/ubuntu 
focal-security InRelease [107 kB]
...
Reading package lists... Done
root@153c1eb1d2c4:/# apt-get install -y figlet
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following NEW packages will be installed:
  figlet
root@153c1eb1d2c4:/# figlet "hello docker"
 _          _ _           _            _
| |__   ___| | | ___   __| | ___   ___| | _____ _ __
| '_ \ / _ \ | |/ _ \ / _` |/ _ \ / __| |/ / _ \ '__|
| | | |  __/ | | (_) | (_| | (_) | (__|   <  __/ |
|_| |_|\___|_|_|\___/ \__,_|\___/ \___|_|\_\___|_|
root@153c1eb1d2c4:/# exit 
[node1] (local) root@192.168.0.23 ~
$ docker ps -a 
ONTAINER ID        IMAGE               COMMAND             CREATED             STATUS                            PORTSNAMES
153c1eb1d2c4        ubuntu              "bash"              6 minutes ago       Exited (127) About a minute ago
$ docker commit --author lqwangxg --message "save as image" 153
sha256:7ff21c05ee7d57d44f7733e0d116080e0ac66c432836211403d82fd18c9ad36f
$ docker images 
EPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
<none>              <none>              7ff21c05ee7d        12 seconds ago      97.2MB
$ docker tag 7ff ubuntu-figlet
$ docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
ubuntu-figlet       latest              7ff21c05ee7d        2 minutes ago       97.2MB