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]: ['c', '6027', 'o', 'h', 'l', '7893', 'u', 'f', '7661', '4715', '1373', '4799', 'd', 'z', '411', '4753', 'd', '8241', '1589', '4173', '3921', 'j', 'o', '5067', '8879', 'e', 'm', '9543', '9625', '855', 'u', 'd', '5859', '4243', '5747', '5147', '7315', 'd', 'x', 'q', '7841', '7397', 'm']
[EX A]: c, d, e, f, h, j, l, m, o, q, u, x, z

[EX Q]: ['v', '3765', '4065', 'a', '4201', 'f', 'x', '9275', 'q', '9303']
[EX A]: a, f, q, v, x

[EX Q]: ['4337', 'i', '9053', '6023', 'i', 'a', '7017', '7675', 'g', '3307', 'y', '7403', 'b']
[EX A]:
a, b, g, i, y