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.

[EX Q]: ['l', 'o', 's', '7411', '7847', '2557', '1977', '2863', '2325', '4177', '4183', '4241', '1005', '1137', '1371', 'v', 'p', 'a', '2453', 'l', '6315', 'l', '6463', 'n', '7645', '9669', '5411', '1631', '5995', 'z', '227']
[EX A]: a, l, n, o, p, s, v, z

[EX Q]: ['575', 'u', 'c', '8113', '2853', '3661', '9427', '3071', '4069', '835', 'w', 't', 'w', 't', 'v', 'g', 'c', '5497', '1703', '8433', 'g', '3545', '2887', 'z', 'a', '2241', '5799', '5915', 'u', '4015', '8327', 'z', 'a', 'w', '8311', '289', '8575', 't', 'b', '2873', 'r', 'z', 'x', '1165', '9881']
[EX A]: a, b, c, g, r, t, u, v, w, x, z

[EX Q]: ['8337', 'r', 'x', 'e', '3203', 'p', 'u', 'i', 'd', '697', 'v', '7221', 'd', 'r', 'e', 'b', 'o', 'y', 'p', '4357', '7713', 'n', '4587', 'y', 'b', 'z', 's', '9257', 'v', 'l', 't', 'q', 'b', '6453', '6025', '1029', 'd', 'n', '4453', 'o', 'y']
[EX A]:
b, d, e, i, l, n, o, p, q, r, s, t, u, v, x, y, z