"preview app run" command removed in latest tools

[megamattron]

Unfortunately it looks like Google has removed the preview app run command in 0.9.89: https://cloud.google.com/sdk/release_notes

I'm trying to figure out how to use your instructions with the dev_appserver.py and will post here if I figure it out. Happy to hear any suggestions if you already know how to do it.

Thanks for the helpful tutorial!