Done (mostly)
-------------
-Add __del__ handlers? I asked for a motivation on python-dev and
-nobody piped up. Yet I expect it will be asked for later. *** Are
-there GC issues? Doesn't the GC make an exception for classic classes
-with a __del__ handler? This part is *not* yet dealt with. ***
+Add __del__ handlers. I asked for a motivation on python-dev and
+nobody piped up. Yet I expect it will be asked for later. There
+were some GC issues, but these have now also been dealt with, thanks
+to Neil Schemenauer.
Assignment to __dict__.