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:
['1931', 'c', 's', '8767', 'z', '8977', '9249', '365', 'p', '7187', 'p', '961', 'k', 'k', '423', '5999', '4697', '6251', '6441', '1821', 's', 's', 'f', '5365', 'z', '5113', 'y', 'k', 'i', '5627', 'u', 'w', '4103', '8035', '7105', 'o', 'n', 's', 'y']

Ex Output:
c, f, i, k, n, o, p, s, u, w, y, z


Ex Input:
['d', 'g', '9019', '9987', '8713', '9513', 'a', '2043', 'd', '5817', 'w', 'd']

Ex Output:
a, d, g, w


Ex Input:
['3955', 'y', 'c', 'x', 'm', '6623', '5567', '4133', 'r', '8961', 'i', 'q', 'z', 'm', 'a', 'r', '9569', '2353', '7809', '1147', 'z', '559', 'l', '3617', '6133', 'l', 'g', 'k', 'm', 'r', 'z', 's', '8795', '2521', 'd', '3535', 'w', 'b', '7993', 'i']

Ex Output:

a, b, c, d, g, i, k, l, m, q, r, s, w, x, y, z