Gimp to YAML: Texture coordinates

I wrote a small PythonFu to easily transfer textures using the layer data from multitextures prepared in the Gimp

Texture coordinates
Texture coordinates

PythonFu saves visible layers above as a PNG image, then wrotes coordinates of, again, visible layers to YAML as below. I will use this in my UI library which is going to use YAML and ChaiScript. Also I am planning to make whole game configuration with these two.

load: Untitled.png
textures:
- coords:
  - [0, 20, 20, 20]
  - [20, 20, 20, 20]
  name: button
  type: imagelist
- coords:
  - [0, 0, 20, 20]
  - [20, 0, 20, 20]
  name: Layer Group
  type: imagelist
- coords: [0, 0, 640, 400]
  name: Background
  type: image