def normalize_indices(self, indices: tf.Tensor) -> tf.Tensor:
        """
        Remove -1 in indices by replacing them with blanks
        Args:
            indices (tf.Tensor): shape any

        Returns:
            tf.Tensor: normalized indices with shape same as indices
        """
        with tf.name_scope("normalize_indices"):
            minus_one = -1 * tf.ones_like(indices, dtype=tf.int32)
            blank_like = self.blank * tf.ones_like(indices, dtype=tf.int32)
            return tf.where(tf.equal(indices, minus_one), blank_like, indices)

        Remove -1 in indices by replacing them with blanks
        Args:
            indices (tf.Tensor): shape any

        Returns:
            tf.Tensor: normalized indices with shape same as indices
        
tensorflow_asr/tokenizers.py