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]: ['t', 'h', '6141', 'g', 'f', 'z', 'n', 'b', 'k', '9059', 'y', 'p', '4289', '2683', 'a', '3267', 'w', 'p', 't', '3623', '7759', 'a', 'o', 'm', '9815', 'q', 'u', '8051', '6871']
[A]: a, b, f, g, h, k, m, n, o, p, q, t, u, w, y, z


[Q]: ['u', 'd', '4193', '5687', 'p', 'r', '7787', 't']
[A]: d, p, r, t, u


[Q]: ['8923', 'i', 'r', 'd', '1413', '1197', 'd', '7777', '8523', '7285', '655', '2291', '6539', '3127', '329', '3443', '3157', 'r', '1881', '551', '8785', 'm', '8723', 'n', '7153', '4733', 'm', '4903', '1151', '4893', 'x', '1561', 'f', '39', 'k', '9977', 'm', '9195', 'w', '3905', '1631', 'l', '1453']
[A]:
d, f, i, k, l, m, n, r, w, x