{
  "version": "0.1",
  "nodes": {
    "1": {"id": 1, "name": "main_block", "op": {"type": "Cube", "size": {"x": 50, "y": 30, "z": 20}}},
    "2": {"id": 2, "name": "main_block_centered", "op": {"type": "Translate", "child": 1, "offset": {"x": -25, "y": -15, "z": 0}}},
    "3": {"id": 3, "name": "cut_block", "op": {"type": "Cube", "size": {"x": 25, "y": 30, "z": 10}}},
    "4": {"id": 4, "name": "cut_block_positioned", "op": {"type": "Translate", "child": 3, "offset": {"x": 0, "y": -15, "z": 10}}},
    "5": {"id": 5, "name": "stepped_block", "op": {"type": "Difference", "left": 2, "right": 4}}
  },
  "materials": {},
  "part_materials": {},
  "roots": [{"root": 5, "material": "default"}]
}