It's not exposed to Ruby, yet. You can add a module function to in `modules/topaz.py` that calls space.convert_type, or add a Ruby file with the logic from https://github.com/rubinius/rubinius/blob/c31e1d3a95f5ae623a00bc4c912f47a56482f82d/kernel/common/type.rb#L19. I would prefer the first option, but I'm not sure.