Hi, I looked more in detail on what would be needed to port numpy to py3k. In particular, I was interested at the possible strategies to keep one single codebase for both python 2.x and python 3.x. The first step is to remove all py3k warnings reported by python 2.6. A couple of recurrent problems - reduce is removed in py3k - print is removed - some exceptions constructions are not allowed I think a first step would be to add a compatibility module to remove any use of print/reduce in the numpy codebase (should not be too difficult). For reduce, we could import functools from python code (functools is not available in python 2.4). Unless someone has an objection, I will import functools code, make it compile for python 2.4 and above, and remove all builtin reduce calls in numpy. Another problem is related to nose: there is an experimental branch for nose which supports py3k, but nose <= 1.0 will not support py3k. The nose author intend to support py3k in a version > 1.0, at which point he will only support python 2.6 and above. I don't know what to do with this (include our own nose in numpy for version < 2.6 - giving up support for python < 2.6 does not sound like a realistic option in the next few years). cheers, David