Repeated indexes into a collection yield different objects each time

This is the problem:

>>> b.bug_tasks[2] is b.bug_tasks[2]
False

A lazr.restfulclient scoped collection object is a lazy collection. If you ask for element 2, it will make an HTTP request to /bugs/549305/bug_tasks?ws.start=2, grab element #2, and wrap it in a Python object. If you ask for element 2 again, it will make another HTTP request and wrap the result in another Python object. If you set bug_tasks[2].status, the field will be set, but you'll never see that object again, because you didn't hold a reference to it.

Semi-obvious solutions include caching individual elements of scoped collections in the scoped-collection object (a solution distinct from caching HTTP requests for scoped collection pages, and probably easier to implement).

The workaround is to assign an object to a variable if you're going to use it more than once.

I think I'd like to have this addressed with a weakref value dictionary as a cache in the Launchpad instance. That would mean a mapping from objects' self_link values to weakrefs of the objects. If the weakref exists, it should be verified to still exist, updated, and returned, so that existence checks like this one work as expected.