Code review comment for lp:~jml/launchpad/list-ec2-test-runs-721784

This is a good start. I'd like to see some tests of cmd_list, especially format_summary and format_instance, but that can wait for a follow-up.

I don't think you need to call .replace(tzinfo=UTC) on datetime.utcnow(), but it doesn't hurt.

I think using 'success: True' to describe a run that's been successful *so far* might give people the wrong impression? Is there an easy way to distinguish between the case when you list a run that's shutting down after a complete success and a run that just hasn't failed yet?