code: public void revertLabels(@NonNull INDArray labels, INDArray mask, int output) {
          if (isFitLabel()) {
              strategy.revert(labels, mask, getLabelStats(output));
          }
      }
docs: Undo (revert) the normalization applied by this normalizer to a specific labels array.
  If labels normalization is disabled (i.e., {@link #isFitLabel()} == false) then this is a no-op.
  Can also be used to undo normalization for network output arrays, in the case of regression.
  
  @param labels Labels arrays to revert the normalization on
  @param output the index of the array to revert