Attaching the whole file isn't a step in the right direction.  The 
preferred approach is to isolate the problem as tightly as possible.

This report is dubious because, I can't get the following to fail:

from random import seed, randint
seed('mystart')
while 1:
   assert 0 <= randint(0, 1452) <= 1452

There is also no failure with:

preshuffle = [None] * 1453
while 1:
   assert 0 <= randint(0, len(preshuffle)-1) <= 1452

Make sure that PWRand.randint() really does call randint() and not 
randrange() and that it doesn't adjust the range of inputs.