GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
#g4 f2 z1 5x5 0 1 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 1 5x5 0 0 -1 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 1 0 0 0 0 0 1 5x5 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 -1 0 0 0 1 0 5x5 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 -1 0 0 0 0 0 1 5x5 1 0 0 0 0 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 5x5 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 1 5x5 1 0 0 0 0 1 1 0 0 0 0 -1 1 0 0 0 0 -1 1 1 0 0 0 -1 1 2^7*3=384 dim5/3;2-1b