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.

['x', 'b', '1467', 'y', '2101', 'y', 'm', '2745', 'z', '429', '7523', 'e', 'f']
b, e, f, m, x, y, z

['f', '217', '449', 't', 'j', '4097', '5561', '8317', '647', 'u', 'b', '7833', 'r', '9011', 'z', '2753', '2183', 'z', 'o', 'g', '7541', 'b', '8795', '327', 'v', 'e', 't', 'l', '4909', 'k', '7681', 'r']
b, e, f, g, j, k, l, o, r, t, u, v, z

['8169', '5385', 'n', 'd', '2067', '9913', '4647', '8893', 'g', '6531', '3667', 'm', 'z', 'l', '7081', 'z', '1041', '1111', '8879', 'z', 'n', '5637', 'k', 't', 'j', '1755', 'p', 'g', '8713', 'w', '8303', '3193', 'z', 'i', '6421', 'p', '7551', '6543', '5361', 'p', '4935', 'b', '1855', '9205', 'u']

b, d, g, i, j, k, l, m, n, p, t, u, w, z