python sort a list using defined order

1>>> sorted(A, key = lambda i: B.index(i[0]))
2[[6, 1], [1, 3], [3, 5]]
3

1>>> A = [[3,5],[1,3],[6,1]]
2>>> B = [6,1,3]
3>>> srt = {b: i for i, b in enumerate(B)}
4>>> sorted(A, key=lambda x: srt[x[0]])
5[[6, 1], [1, 3], [3, 5]]
6