How to set colors for layers independently from script

[avlsi]

I would like to set color independently as I am also using this package for drawing floorplan.

Floorplan will look good with different colors.

Example Code, suppose I want 20 blocks to be placed at different locations.
I am increasing layer by 1 for each block. I want colors of these layer set independently.

layer=layer+1
cell = core.Boundary(points,layer=layer)

Let me know how can I do it?