The code in this module is derived from the "factor" program in
coreutils.

To install, run

   # python setup.py install

This will create the python module "factor", with one method,
factor().

factor.factor() takes an integer and returns a list of its prime
factors, very similar to the output of /usr/bin/factor.

At the moment, factor.factor() will raise an OverflowError if its
input is 2^31 or greater. This is an unsolved bug.