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]: ['w', 'i', '4383', '7667', '9617', 'y', 'a', '8051', 'w', '4857', 'y', '3953', 'u', 'o', 'y', 'i', '9201', 'g', '1807', '5367', 'g', '5263', '3995', '6665', '3113', '9433', '6315', 'm', '845', 'x', 'c', 'v', 'h', '1491', 'g', '3519', 'x', 'b', '7695']
[EX A]: a, b, c, g, h, i, m, o, u, v, w, x, y

[EX Q]: ['7799', '8163', '3389', 'x', 'k', 'm', '6085', 'f', '1131']
[EX A]: f, k, m, x

[EX Q]: ['5387', '1561', '9413', '6459', '3', 'g', 'v', '9051', '7757', '2091', 'h', '7071', '4057', 'z', '163', 'q', '8909', '8425', 'j', '3995', 'b', 't', '1457']
[EX A]:
b, g, h, j, q, t, v, z