def last_phi(self):
        """Return the most recent phi (sequence of image frames)."""
        indexes = np.arange(self.phi_length - self.top, self.top)
        return self.imgs.take(indexes, axis=0, mode='wrap')
dataset/ETHPy150Open spragunr/deep_q_rl/deep_q_rl/ale_data_set.py/DataSet.last_phi/swapped operands of `-`