I'm attempting to set up and run the basic code sample (python version) found here.
Unfortunately the provided login page fails to resolve (http://lms.valence.desire2learn.com/). Is there a different sample host I can use to verify my setup?
You are correct; that test host has been retired and replaced by a new one that's associated with the Brightspace Developer Community. To use it, you will need to be a Developer Community member and use a test user provisioned on the new developer environment host.