You can create a MaterialPartColorSupplier form a MaterialPart object, which will then be used whenever requested.

Importing the class

Should you need to import he class, here you go:

import mods.contenttweaker.MaterialPartColorSupplier;

Static methods

Static methods can be called upon the package, not upon instances of the class.

//mods.contenttweaker.MaterialPartColorSupplier.create(IMaterialPart materialPart);