So I didn't look carefully and I installed 64 bit Python2.7 on an OS X 10.5 box. This didn't work with the standard cryptic wrong-OS message "dyld: unknown required load command"
OK, fair enough
So I dragged the Python2.7 icon to the trash from Applications; then I went in with sudo and renamed the
/Library/Frameworks/Python.framework/Versions/2.7/
to
/Library/Frameworks/Python.framework/Versions/2.7BROKEN/
and installed the 32-bit Python 2.7. But I am still getting the "dyld" error. Any idea what other side effect the broken install might have had to make this possible and how I can fix it?
Problem solved by following this bug report's instructions, substituting 2.7 for 2.6 everywhere, then reinstalling.