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:
['w', '5341', 'b', '6243', 'v', '877', '1087', '6763', '5241', '3369', '9119', 't', 'v', 'j', '8261', 'o', 'b']

Ex Output:
b, j, o, t, v, w


Ex Input:
['u', 'w', '401', 't', 'g', 'h', 'g', '8073', '9597', '1347', '7835', '5007', '977', 'p', '7679', 'b', '4883', '4931', '999', 'r', '1181', 'x', '2063', 'l', 'w', 'i', 'l', 'x', 'i', '9057', '5007', 'w', '743', '1635', 'y', 'f', '9227', 'z', '5227', 'd', '7129', 'k', '7657']

Ex Output:
b, d, f, g, h, i, k, l, p, r, t, u, w, x, y, z


Ex Input:
['4697', 'm', '3119', 'f', 'n', '4029', '1011', '5473', '7121', '1321', '1367', 's', 'k', 'a', 'o', 'l', '1551', 'n', '4333', 'u', '7157', 'f', '9999', 'z', 'x', 'o', 'y', 'a', 'a', '1195', 'h', '4343', 'l', 'v', 'y', 's', 'b', 'h', '3403', 'p', 'k', '479', 'd', 'i']

Ex Output:

a, b, d, f, h, i, k, l, m, n, o, p, s, u, v, x, y, z