sample

    def sample(self, seed, n_sample):
        h = np.zeros((1, self.hidden_size))
        seed = one_hotify(seed, self.vocab_size)
        for char in seed:
            h = self.step_forward(char[None,...], h)

        o = self.output([h])[0]
        o_seq = []
        for i in range(n_sample):
            h = self.step_forward(o, h)
            o = self.output([h])[0]
            o_seq.append(np.argmax(o))
        return np.array(o_seq)