Error when converting 00511440.h5 to .step file

[doralune]

util/export2step.py becomes error below for 00511440.h5, but fine for 00511440.json

AttributeError: 'NoneType' object has no attribute 'IsNull'

I recreated the h5 file by dataset/json2vec.py, ran util/export2step.py again and got the same error.
Something might have been different when converting from json to h5.

For 00511440.h5, the body in create_CAD() was None after the last step of ['NewBodyFeatureOperation', 'JoinFeatureOperation', 'NewBodyFeatureOperation', 'JoinFeatureOperation'].

DeepCAD/cadlib/visualize.py

Lines 25 to 37 in f7b3507

	def create_CAD(cad_seq: CADSequence):
	"""create a 3D CAD model from CADSequence. Only support extrude with boolean operation."""
	body = create_by_extrude(cad_seq.seq[0])
	for extrude_op in cad_seq.seq[1:]:
	new_body = create_by_extrude(extrude_op)
	if extrude_op.operation == EXTRUDE_OPERATIONS.index("NewBodyFeatureOperation") or \
	extrude_op.operation == EXTRUDE_OPERATIONS.index("JoinFeatureOperation"):
	body = BRepAlgoAPI_Fuse(body, new_body).Shape()
	elif extrude_op.operation == EXTRUDE_OPERATIONS.index("CutFeatureOperation"):
	body = BRepAlgoAPI_Cut(body, new_body).Shape()
	elif extrude_op.operation == EXTRUDE_OPERATIONS.index("IntersectFeatureOperation"):
	body = BRepAlgoAPI_Common(body, new_body).Shape()
	return body