There is no python command in the API for that.
You can only replace the whole object.
Here an example in Logic Briks.
try from 3 hour,not work the link
I must change the object? O.O
On my computer the link is working.
NoGhostToGhost.blend (266 KB)
that is an other object
i want change (if possible) ghost/no gost of the same object
As I have written in the second post that is not possible. You need to change the object.
ok, I understood that you could not -with python-