[Edu-sig] Technical question

[Kirby Urner]

I have a pyfraction.py and a polynomial.py, which contain
Fraction and Poly classes respectively.

My problem is each class needs to know about the other, 
meaning I'm now doing an isinstance(other,Fraction) in 
Poly, and an isinstance(other,Poly) in Fraction.

So how do I handle this.  I have an 

     import Fraction from pyfraction 

at the top of polynomial.py, and an 

     import Poly from polynomial

at the top of pyfraction.py  

This is obviously NOT the way to handle it, because
it's a loop.  In trying to import Fraction, it hits the
line to import polynomial, which it's still trying to 
deal with.

This problem arises now that I'm using isinstance(foo,bar)
and need bar as a global.  Earlier, I was doing 
type(foo).__class__.__name__ == "bar", which was ugly,
but didn't require that I actually have any bars hangin'
around.

Kirby