There are four files you can download. The ones with "nopy" in their filename are just the Python code for Jetscript, packaged as a .zip or a .tar.gz (but they're the same code). The large (9 MB?) files include the Python 2.3.4 distribution too -- the "-win" one has the Python installer for Win32, whereas the "-unix" one has the Python source as a .tar. Of course, if you're running a Linux system, Python may be available packaged from your distributor.