code: def labels_last_to_blankid(labels, blank_index, num_class=None):
      """Change the value of blank_label elements from num_classes - 1 to blank_index,
      after removing blank_index by decoder."""
      labels = transform_preprocess(
          labels=labels, blank_index=blank_index, num_class=num_class
      )
  
      labels_values = labels.values
      labels_change_blank_id = tf.where(
          labels_values >= blank_index, labels_values + 1, labels_values
      )
  
      labels = tf.SparseTensor(
          indices=labels.indices,
          values=labels_change_blank_id,
          dense_shape=labels.dense_shape,
      )
  
      return labels
  
imports: import delta.compat
label_desc: Use image node_id 4 for calling a global function with example usage: labels_last_to_blankid(labels, blank_index, num_class) and returns: labels