How to get/set AutoCAD Mechanical scale in a program or script?

To get or set the modelspace scale variable in AutoCAD Mechanical (as in the AMTITLE or AMCONFIG commands) from your user program (application, routine) or menu script, you can use the following LISP functions:

(gengetdwgsetting "scale")
(gensetdwgsetting "scale" "1:10")

or

(amggetdwgsetting "scale")
(amgsetdwgsetting "scale" "1:3")