Of course, I'm not talking about something that would transform any Python code into semantically JavaScript code, but simply something that would analyze a "restricted" Python source file, and spit out equivalent JavaScript. The big advantage (as far as I'm concerned) is that one could make use of some of the syntactic shortcuts that JavaScript doesn't offer, that the Python syntax checker generally does a better job than the JS one, and (perhaps most importantly) this could be configured to put in 'instrumentation', such as checks to make sure than an attempt to access an undefined attribute actually throws an error.
Color me curious, Ken -- http://mail.python.org/mailman/listinfo/python-list