def METHOD_NAME(self):
    p = PropertyTree()
    p.here = 3.0
    p.there.now = 4.0
    p.deeper.test.path = 5.0
    p.lock()
    self.assertEqual(p.here,3.0)
    self.assertEqual(p.there.now,4.0)
    self.assertEqual(p.deeper.test.path,5.0)
    self.assertRaises(AttributeError,p.__getitem__,"bad")
    self.assertRaises(AttributeError,p.__getitem__,"bad/deeper/path")
    self.assertRaises(AttributeError,p.__getattr__,"bad")
    self.assertRaises(AttributeError,p.there.__getattr__,"bad")
    self.assertEqual(p.deeper.test._locked,True)