Create Chamfer by distances

 1from salome.shaper import model
 2
 3model.begin()
 4partSet = model.moduleDocument()
 5Part_1 = model.addPart(partSet)
 6Part_1_doc = Part_1.document()
 7Box_1 = model.addBox(Part_1_doc, 20, 20, 20)
 8Chamfer_1 = model.addChamfer(Part_1_doc, [model.selection("FACE", "Box_1_1/Top")], True, 2, 2)
 9model.do()
10model.end()

Download this script