Recolor as a Curve Tool

Hello. Im working on recoloring script. I need to script a Curve Tool. There must be a function that do the work.

I tried a Phantasm Curve Tool, but it breaks objects into a trash too often. So, I just want to use it for preview - to tweak a color and use input and output numbers of curves to do the same job in my script.

This red graphs are rotated curves of Curve Tool by 45 degrees clockwise. They have wrong numbers on black line, cause it should be moved left because of rotation. Anyway, it could do the job well, I guess.