def METHOD_NAME(self):
    with self.assertRaises(Exception) as e1:
        Checkpoint(dir_path="dir_path", steps=0, max_to_keep=1)
    self.assertEqual("Argument 'steps' is not a positive integer", str(e1.exception))
    with self.assertRaises(Exception) as e2:
        checkpoint = Checkpoint(dir_path="dir_path", steps=1000, max_to_keep=1)
        checkpoint.steps = 0
    self.assertEqual("Argument at position 0 is not a positive integer", str(e2.exception))