def METHOD_NAME(n, bs):
    im = IndexMap(MPI.COMM_WORLD, n)
    sp = SparsityPattern(MPI.COMM_WORLD, [im, im], [bs, bs])
    if bs == 1:
        for i in range(2):
            for j in range(2):
                sp.insert(2 + i, 4 + j)
    elif bs == 2:
        sp.insert(1, 2)
    sp.finalize()
    return sp