code: public static DenseTensor random(int[] dimensions, int[] sizes, double mean, double stddev) {
      DenseTensorBuilder builder = new DenseTensorBuilder(dimensions, sizes);
      Iterator<KeyValue> keyValueIter = builder.keyValueIterator();
      Random random = Pseudorandom.get();
      while (keyValueIter.hasNext()) {
        builder.put(keyValueIter.next().getKey(), (random.nextGaussian() * stddev) + mean);
      }
      return builder.buildNoCopy();
    }
docs: Constructs a random tensor spanning {@code dimensions} each with size
  {@code sizes}. Each entry of the tensor is drawn independently at random
  from a gaussian with {@code mean} and standard deviation {@code stddev}.
  
  @param dimensions
  @param sizes
  @param mean
  @param stddev
  @return