def METHOD_NAME(self):
    x = X()
    self.assertIsInstance(x, X)
    self.assertEqual(len(x), 1)
    x = X.Empty()
    self.assertIsInstance(x, X)
    self.assertEqual(len(x), 0)
    x = X.Alloc(10)
    self.assertIsInstance(x, X)
    self.assertEqual(len(x), 10)
    for xx in x:
        self.assertEqual(xx.A, 0)