Changing basenote for slicing

Anyone knows what would be command to change basenote from which slices keyzones will start?
it is not same as (…).sample[1].sample_mapping.base_note, after i change it when creating first slices everything is back to previous settings (c3 in my case)

Go to the keyzones settings…change the “drum kit” basenote at the upper right…hit the drum kit button for it to take action…

Yeah, thats where it is in the gui, but i want to change it through lua api.