"best" rational number library for Python?

[skip at pobox.com]

A guy at work asked for functionality commonly found with rational numbers,
so I said I'd find and install something.  I figured gmpy would be suitable,
alas I'm having trouble successfully building the underlying GMP 4.2.1
library on a PC running Solaris 10 (won't compile with the default --host,
fails "make check" if I go the no-assembly route).  Before I invest a bunch
of time into this, am I barking up the wrong tree?

Performance is, for now, certainly not an issue.  Even a pure Python
rational number class would probably suffice.

Thx,

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