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 Input:
['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 Output:
c, d, e, f, h, j, l, m, o, q, u, x, z


Ex Input:
['4637', 'f', '2639', '8623', 'w', 'e', 'k', '5503', 'x', '6633', '7553', '1455', 'u', '1773', 'r', 'u', '1489', 'u', '1303', '9683', 'z', '565', '7041', 'x', 'z', '9431', 'k', 'v', 'j', 'z', '5469', '5665', '4089', '4951', '8263', '5675', '4095', '7745', 'z', '2437', 'd', 'e', 'w']

Ex Output:
d, e, f, j, k, r, u, v, w, x, z


Ex Input:
['3329', 'u', '8357', '977', 'd', 'a', 'w', '7747', 'm', 'f', 'o', '4131', '8633', 'h', 'a', 'k']

Ex Output:

a, d, f, h, k, m, o, u, w