def test_ancestor(self): m1 = MeiElement("music") musicid = m1.id b1 = MeiElement("body") bodyid = b1.id s1 = MeiElement("staff") n1 = MeiElement("note") a1 = MeiElement("accid") m1.addChild(b1) b1.addChild(s1) s1.addChild(n1) n1.addChild(a1) self.assertEqual(bodyid, a1.getAncestor("body").id) self.assertEqual(musicid, a1.getAncestor("music").id) self.assertEqual(None, a1.getAncestor("mei"))