import tensorflow as tf


        self.max_p_len = config.max_p_len
        self.max_q_len = config.max_q_len
        self.max_a_len = config.max_a_len

        # the vocab
        self.vocab = vocab

        # session info
        sess_config = tf.ConfigProto()
        sess_config.gpu_options.allow_growth = False
        self.sess = tf.Session(config=sess_config)

        self._build_graph()

        # save info
        self.saver = tf.train.Saver()

        # initialize the model
        self.sess.run(tf.global_variables_initializer())

    def _build_graph(self):
