Hi,
It worked for me; I hope it helps:
a = torch.tensor([[[ 1,  2,  3,  4,  5,  6],
                   [ 7,  8,  9, 10, 11, 12],
                   [13, 14, 15, 16, 17, 18],
                   [19, 20, 21, 22, 23, 24]]])
z= a.unsqueeze(0).unfold(2, 2, 2)[0].unfold(2, 2, 2).contiguous().view(1, 6, 2, 2)


Bests