import tensorflow as tf

        # nwords = tf.feature_column.input_layer({'words_len': raw_nwords}, params['words_len_feature_columns'])
        # nwords = tf.reshape(nwords, [-1])
        # nwords = tf.to_int32(nwords)

        # words = features['words']
        # words = tf.convert_to_tensor(words)
        #
        # nwords = features['words_len']
        # nwords = tf.convert_to_tensor(nwords)

        nwords = tf.identity(self.features["words_len"], name="input_words_len")

        # get tag info
        # with Path(self.params['tags']).open() as f:
        indices = [
            idx
            for idx, tag in enumerate(self.params["tags_data"])
            if tag.strip() != "O"
        ]
        num_tags = len(indices) + 1
