def test_descendants(self): m1 = MeiElement("music") b1 = MeiElement("body") s1 = MeiElement("staff") n1 = MeiElement("note") a1 = MeiElement("accid") m1.addChild(b1) b1.addChild(s1) s1.addChild(n1) n1.addChild(a1) desc = m1.getDescendants() self.assertEqual(4, len(desc)) desc2 = a1.getDescendants() self.assertEqual(0, len(desc2))