Equal sets with unequal print and str() representations

[Ganesh Gopalakrishnan]

This probably is known, but a potential pitfall (was, for me)
nevertheless. I suspect it is due to hash collisions between 's3' and
's13' in this case? It happens only rarely, depending on the contents of
the set.
S1
{'s8', 's13', 's2', 's0', 's7', 's6', 's4', 's3', 's14'}S2
{'s8', 's3', 's2', 's0', 's7', 's6', 's4', 's13', 's14'}

S1==S2
True

str(S1)
"{'s8', 's13', 's2', 's0', 's7', 's6', 's4', 's3', 's14'}"str(S2)
"{'s8', 's3', 's2', 's0', 's7', 's6', 's4', 's13', 's14'}"False

 

[Ganesh Gopalakrishnan]

Thanks to all who replied - also to Ben. I had foolishly assumed that
the same set exhibits the same rep on at least one platform. Like any
bug, the falsity of my assumption took months to expose - till then,
things had worked fine. Needless to say I'm new to Python. (The double
printing is because I tend to work within an Emacs inferior shell.)

Cheers,

Ganesh