4106.sagews

rats=[(1,2),(3,5),(8,13)]

[(a+b/a)for (a,b) in rats]

[3, 14/3, 77/8]

[(a,a+b)for (a,b) in rats]

[(1, 3), (3, 8), (8, 21)]

[((a,a+b), (a+b,b)) for (a,b) in rats]

[((1, 3), (3, 2)), ((3, 8), (8, 5)), ((8, 21), (21, 13))]