import tensorflow as tf

        self.features = tf.placeholder(tf.float32, [None, self.L, self.D])
        self.captions = tf.placeholder(tf.int32, [None, self.T + 1])
    
    def _get_initial_lstm(self, features):
        with tf.variable_scope('initial_lstm'):
            features_mean = tf.reduce_mean(features, 1)

            w_h = tf.get_variable('w_h', [self.D, self.H], initializer=self.weight_initializer)
