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:
['n', 'g', 'u', '2873', 'k', '4411', 'w', '8179', 'w', 'w', 'f', 'g', 'e', '7837', '3055', 'z', 's', '6037', 'n', '1479', 'c', '5311', 'i', 'w', 'z', '1891', '9663', 'y', 'f', 'h']

Ex Output:
c, e, f, g, h, i, k, n, s, u, w, y, z


Ex Input:
['f', '6817', 'f', 'd', '3835', '3051', 'u', 'l', '7679', 'b', '3931', '1441', 'q', '8675', 's', '5487', 'y', '2279', 'x', 'y', '9513', '2875', '1771', '879', '2927', '3469', 'v', 't', 'k', '9991', '2565', '7345', '973', 'w', 'i', '6105']

Ex Output:
b, d, f, i, k, l, q, s, t, u, v, w, x, y


Ex Input:
['1795', 'b', 'w', '6527', 'n', '5847', 'r', '509', '7053', '8263', '8629', 'm', '6413', 'k', 'o', 'b', '6541', '1287', 'u', 'v', 'f', 's', 'q', '5453', '1273', '1641', 'n', 'd', 'm', 'l', '8667', '3365', 'v', '4655', 'd', '9251', 'm']

Ex Output:

b, d, f, k, l, m, n, o, q, r, s, u, v, w