it's not that hard actually,
maybe take the original
avs script as reference would be much easier
it's almost a copy paste styleee work
sstr = string (sstr) ----- sstr = repr (sstr)
mt_lutxy (c,b,xxxxxxxx) ---- core.std.Expr ([c,b],["xxxxxxx"])
and to make the 8bpc expr work at 16bpc
x ----- x 256 /
y ----- y 256 /
z ----- z 256 /
and add 256 * at the end of the expr