2. Build an image and push it to a regisry

docker build -t ml .

gcptestuser33@cloudshell:~/ml (pivotal-diorama-291019)$ docker images
REPOSITORY   TAG        IMAGE ID       CREATED          SIZE
ml           latest     b2a3b642e922   36 seconds ago   1.01GB
python       3.6-slim   fadbffa5af00   10 days ago      112MB

docker tag ml gcr.io/pivotal-diorama-291019/ml:public

gcptestuser33@cloudshell:~/ml (pivotal-diorama-291019)$ docker images
REPOSITORY                         TAG        IMAGE ID       CREATED         SIZE
ml                                 latest     b2a3b642e922   3 minutes ago   1.01GB
gcr.io/pivotal-diorama-291019/ml   latest     b2a3b642e922   3 minutes ago   1.01GB
python                             3.6-slim   fadbffa5af00   10 days ago     112MB

docker push gcr.io/pivotal-diorama-291019/ml:public