mesh.Tetrahedron()
mesh.Compute()
# get all badly oriented volumes
-filter = smesh.GetFilter(smesh.VOLUME, smesh.FT_BadOrientedVolume)
+filter = smesh.GetFilter(SMESH.VOLUME, SMESH.FT_BadOrientedVolume)
ids = mesh.GetIdsFromFilter(filter)
-print "Number of badly oriented volumes:", len(ids)
+print("Number of badly oriented volumes:", len(ids))