Replace the row with a norm of 0 in the tensor with the corresponding row in another tensor

I now have a pytorch tensor A of dimensions (2000, 1, 360, 3). I'm trying to find all indexes with norms of 0 in the last dimension of this tensor. And replace these positions with the values of the corresponding positions in another tensor B (the same dimension as A).

Example (A, B: (2, 1, 3, 3))

A = [[[[0, 0, 0],  # norm == 0       [1, 2, 1],       [0, 1, 0]]],     [[[2, 0, 0],       [0, 0, 0],  # norm == 0       [1, 1, 1]]]]B = [[[[0, 0, 1],       [1, 1, 1],       [0, 1, 0]]],     [[[1, 0, 0],       [0, 1, 1],       [2, 1, 1]]]]

Expected result:

new_A = [[[[0, 0, 1],   # <-- replaced           [1, 2, 1],           [0, 1, 0]]],         [[[2, 0, 0],           [0, 1, 1],   # <-- replaced           [1, 1, 1]]]]