Using layer.extrusion in a Python script

[clc]

I am developing a Python script tool to transform a 2D feature class into a multipatch.

Right now, I have to split the script into 2 scripts and manually do the extrusion, because I cannot figure out how to make the extrusion based on a field. I could apply a fixed extrusion by writing:

expression = "5"

lyr.extrusion("BASE_HEIGHT", expression)

But I would like a extrusion based on one of the field of my feature class (and also set the unit as it is possible in the Feature Layer Tab in Pro). I tried (among other combinations):

expression = "!Extrusion_ft! / 3.28084"

lyr.extrusion("BASE_HEIGHT", expression)

The script runs without error but no extrusion...

Thanks for any help.

[WilliamLee]

I have been looking for a solution like this for quite some time. Thank you @AnonymousUser23 and @clc for sharing your code and solutions. The [isFlattened = "false"] was also key in my testing. Thank you both!