The docs say it is an error to start a threading thread more than once, but they do not specify exactly what exception will be raised.

Apparently it is always AssertionError (though an expert should verify this).

It would be very helpful to document the exception because there is no other documented way to tell if a threading thread has been started than to try to start it.

I posted to the dev group on 2003-02-24 about this and Aahz asked me to file a doc bug. So here it is.

I suggest the info go in the Thread object docs, in the documentation for "start".