Message 85906 - Python tracker

This is a duplicate of 4799, which I've closed.

I've resisted fixing this because differences in various platform
sprintf's have made it difficult. Now that Mark Dickinson and I are
close to removing the use of sprintf for float formatting, I'll have the
tools to deal with this better.

Not sure what this means for 2.7, yet. We're not planning on backporting
the new float formatting to 2.7.