{
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        "size": {"x": 60, "y": 40, "z": 20}
      }
    },
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        "type": "Translate",
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        "offset": {"x": -30, "y": -20, "z": 0}
      }
    }
  },
  "materials": {},
  "part_materials": {},
  "roots": [
    {"root": 2, "material": "default"}
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}