code: public void clearLayerMaskArrays() {
          for (Layer layer : layers) {
              layer.setMaskArray(null);
          }
          this.inputMaskArrays = null;
          this.labelMaskArrays = null;
      }
docs: Remove the mask arrays from all layers.<br>
  See {@link #setLayerMaskArrays(INDArray[], INDArray[])} for details on mask arrays.