But I thought we need to convert them to
x has shape of (2, 3)  to convert to (1 ,2, 3,)
c which is a constant has shape of (4,)  to convert to  (4, 1, 1)
and we get by
y = c.view(-1, 1, 1)

tensor([[[  1,   2,   3],
         [  4,   5,   6]],

        [[ 10,  20,  30],
         [ 40,  50,  60]],

        [[ 11,  22,  33],
         [ 44,  55,  66]],

        [[100, 200, 300],
         [400, 500, 600]]])