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:
['3035', 'f', 'k', 'e', '3023', 'p', '9667', '5277', '4757', '8433', 'g', '1399', '7721', 'n', 'p', '7469', '7581', '5679', 'g', 'q']

Ex Output:
e, f, g, k, n, p, q


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:
['f', '165', 'm', '9975', '9259', '6505', 'a', 'g', 's', '1127', 'h', 'n', 'c', '6475', 'c', '8657', 'a', '4057', 'm', 'y', 'w', 'm', '6567', '7297', '285']

Ex Output:

a, c, f, g, h, m, n, s, w, y