Discussed with David Murray at PyCon Sprints 2015.
Considered the fact that to preserve backwards compatibility, it seems important that rather than
a) merely checking for the presence of each constant string (as the test does now) OR
b) checking for each desired character (regardless of order) as noted in msg221766

the tests should check for the exact strings that have historically been published in Python. Doing so seems to be the right path to ensure that:
a) the strings exist AND
b) the strings have not inadvertently changed.