In this task, you are given an input list A comprising of numbers and alphabets. You need to extract and sort the unique alphabets in the list. The alphabets in the input list will only be in lowercase. Return -1 if there is no alphabet in the input list.

[Q]: ['6737', 'g', '9985', '5257', 'k', 't', '7863', 'y', '8319', 'l', 'o', '6505', '6531', 'z', '3055', '2943', '3625', 'h', '4867']
[A]: g, h, k, l, o, t, y, z


[Q]: ['o', '1217', '449', 'n', 'e', 'o', 't', '9043', '1925', '5687', '7197', '7943', 'u', '5053', 'q', 'e', '89', 'l', 'h', '3083', '4295', 'o', 'n', '6309', '743', 'n', 'j', '2105', 's', '6845', 'p', 'p', '1355', '3757', 'v', 'f', '961', '4623', '4633', 'p', '4593', 'p', '7337', 'o', 'u']
[A]: e, f, h, j, l, n, o, p, q, s, t, u, v


[Q]: ['s', 'a', 'y', 'r', 'e', 'x', '2787', 'o', '4809', 'y', '8397', '3827', 'k', 'z', '4647', 's', 'h', 'w', '4549', 'j', 'w', '5169', 'p', 'm', 't', 'u', 'y', '1499', 'm', '4299', 'y', '5789', 'r', '3919', 'h', 'k', 'v', 'y', '691']
[A]:
a, e, h, j, k, m, o, p, r, s, t, u, v, w, x, y, z