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.

Input: Consider Input: ['1945', 't', '4477', '4439', '6569', '2021', 'y', 't', '2725', '8947', '6921', '1373', '8107', 'g', 'c', 'w', 'x', 'b', '9117', 'k', '6567', '5073', '2307', 'e', 'b', '7405', 'e', 'x', '1419', 'd', 'o', 'n', 'a', '2647', 'z', '1459', 'n', '6137', 'u', 'b', 'q', '4459']

Output: a, b, c, d, e, g, k, n, o, q, t, u, w, x, y, z


Input: Consider Input: ['4945', 'i', 'h', 's', '8925', 'i', '3995', 'f', '813', '1823', '3475', 'q', '2463', '9487', 'c', 'c', 'n', 'y', 's', '6269', 'a', 'u', 'd', 'd', '9291', '3187', '545', '7929', 'd', '1007', '7579', '8421', '4033', 'v', 'c', 'e', 'n', 'j']

Output: a, c, d, e, f, h, i, j, n, q, s, u, v, y


Input: Consider Input: ['b', '4043', 'c', 'n', 'x', 's', '1041', 'h', 'e', 'i', '1303', 'o', 'w', '9807', 'z', 'g', '5293', 'p', 'c', '6841', '6589', '2105', 'f', 'y', 'o', '813', 'e', '2185']


Output: b, c, e, f, g, h, i, n, o, p, s, w, x, y, z