OpenCascade export bug

export-bug.py

import OCC.gp as gp
import OCC.BRepPrimAPI as brep
import OCC.BRepAlgoAPI as brep_alg
import OCC.Utils.DataExchange.IGES as iges
import OCC.Utils.DataExchange.STEP as step
import OCC.Display.SimpleGui as gui

objs = []
for x in [0, 21]:
    ax = gp.gp_Ax2(gp.gp_Pnt(x,0,0), gp.gp_Dir(0,1,0))
    obj = brep.BRepPrimAPI_MakeTorus(ax, 10, 3).Shape()
    objs.append(obj)

obj = brep_alg.BRepAlgoAPI_Fuse(*objs).Shape()
#obj = brep_alg.BRepAlgoAPI_Cut(*objs).Shape()
#obj = brep_alg.BRepAlgoAPI_Common(*objs).Shape()

if 0:
    iges_writer = iges.IGESExporter("two-tori.igs")
    iges_writer.add_shape(obj)
    iges_writer.write_file()

    iges_reader = iges.IGESImporter("two-tori.igs")
    iges_reader.read_file()
    read_obj, = iges_reader.get_shapes()
else:
    step_writer = step.STEPExporter("two-tori.stp")
    step_writer.add_shape(obj)
    step_writer.write_file()

    step_reader = step.STEPImporter("two-tori.stp")
    step_reader.read_file()
    read_obj, = step_reader.get_shapes()

display, start_display, add_menu, add_function_to_menu = gui.init_display()
display.DisplayShape(read_obj, update=True)
start_display()