What kind of conditions could lead to this "Cache values may only be
in one cache." ValueError exception (linked below) on a transaction
I'm seeing this in my error logs  on commit attempt by ZPublisher
in Zope2, but have not seen it before this point, AFAICT.
I have not yet duplicated this myself, but see it in the wild from my
log. This is in an application that saves various persistent record
objects inside BTrees and also uses repoze.catalog/zope.index. I am
using RelStorage 1.6 beta.
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