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:
['v', '2989', 'z', '7843', 'e', '9923', 'y', 'b', '7611', 'u', 'u', '6227', '3145', 'w', '6451', 'g', '3129', 'o', 'r', 'z', '8349', 'u', 'h', 'd', 'g', 'a']

Ex Output:
a, b, d, e, g, h, o, r, u, v, w, y, z


Ex Input:
['4123', '1397', '103', 'w', 't', 'j', '233', '7239', 'b', 'n', 't', '6273', 'l', '1167', '8389', '5609', '9029', '7741', 'o', 'p', '6547', '5593', 'd', '8401', 's', '4243', 's', 'u', 'm', '6659', '5691', '2105', '8897']

Ex Output:
b, d, j, l, m, n, o, p, s, t, u, w


Ex Input:
['4013', 'd', 'm', '6055', '6843', '5105', 't', '9823', 'z', 't', '6499', '3135', '7111', 'z', '3099', '4707', '4011', 'n', '9833', 'g', '1925', '2639', '3039', 'j', 't', 'l', 'c', 'u', 'z', 'm', '8369', '5573', '4157']

Ex Output:

c, d, g, j, l, m, n, t, u, z