{                        'comment can go here: start of input
0,1,2,3,-1,         'this is face 1, vertices 0 1 2 and 3
4,5,6,7,-1,
0,1,5,4,-1,          'another comment
1,2,6,5,-1,
2,3,7,6,-1,
3,0,4,7,-1,
}                       'end of input