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.

['7917', '2295', 'q', 'v', '9373', 'w', 'n', 'q', '5803', 'g', 'k', 'm', '2167', 'k', '6425', 'x', 'g', '341', 't', 'u', '8829', 'h', '4333']
g, h, k, m, n, q, t, u, v, w, x

['y', 'p', 'q', '2157', 'b', 'w', '8875', 'k', 'i', 'd', '9743', '4941', 'b', 'p', '9941', '495', 'h', 'i', '839', 'c', 'h', 'f', 'b', 'a', 'k', 'z', '7549', '4149', 'h', 'j', '1947', 't', 'f', 'c', '1243']
a, b, c, d, f, h, i, j, k, p, q, t, w, y, z

['l', '1073', '6199', '3311', '19', '8961', 'e', 'v', '4583', 'k', '5403', 'k', '2053', '5619', '2915', 'h', '2005', 'q', '637', '3823', '3215', '1793', '2631', 'z', '6531', '277', '8299']

e, h, k, l, q, v, z