code: def json_index_face_set(t):
      from itertools import chain
  
      def flatten(ll):
          return list(chain.from_iterable(ll))
  
      return FaceGeometry(
          vertices=flatten(t["vertices"]),
          face3=flatten(t["face3"]),
          face4=flatten(t["face4"]),
          facen=t["facen"],
      )
  
file_path: pythreejs/pythreejs/sage.py
label_desc: Use image node_id 6 for calling a global function with example usage: json_index_face_set(t) and returns: FaceGeometry, list