docs: public static SDVariable squash(SameDiff SD, SDVariable x, int dim){
          SDVariable squaredNorm = SD.math.square(x).sum(true, dim);
          SDVariable scale = SD.math.sqrt(squaredNorm.plus(1e-5));
          return x.times(squaredNorm).div(squaredNorm.plus(1.0).times(scale));
      }