docs: static INDArray createMask(DataType dataType, long[] shape){
          switch (shape.length){
              case 2: // FF-Type input
                  return Nd4j.ones(dataType,shape[0], 1);
              case 3: // RNN-Type input
                  return Nd4j.ones(dataType, shape[0], shape[2]);
              case 4: //CNN input
                  return Nd4j.ones(dataType, shape[0], 1, 1, 1);
              default:
                  Preconditions.throwEx("Can not create all-ones-mask for given input shape %s.", Arrays.toString(shape));
                  return null;
          }
      }