audio input?

[Tally]

I am writing a nifty app that plays a series of sinewaves at different
frequencies where they are fed into a simple circuit involving either
an inductor or capacitor of unknown value. Another waveform is read
back in via the Line In of the computer and through various little
tricks my Python program will calculate the inductance or capitance of
the part.

So... I've checked out PySnack, and it doesn't do what I want. Does
anyone know of a clean, simple audio library or wrapper for Python
that is friendly to capturing low-latency audio to memory? It would be
nice if it had functions like RMS power and that kind of thing but I
can always write that myself in C...

Thanks for your time,
Tally