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:
['s', '6723', 'l', '1573', '1129', 'n', '4277', '5003', 'y', '7563', 'c', '6747', '3105', 's', '3593', '8417', '8253', '4157', 'w', 'f', 'z', 'd', '9685', '1033', 'h', '4893', 't', 'j', '6821', 'z', 'a', 'u', '591', 'o', '1087', '2147', '1223', '2339', 'i', 'y', '9307', 'x', 'z', 'r', 'y']

Ex Output:
a, c, d, f, h, i, j, l, n, o, r, s, t, u, w, x, y, z


Ex Input:
['k', '1995', 'b', '2581', 'x', '2639', 'i', '6761', '2701', 'd', '6993', '9375', 'r', 'm', '249', '8115', '8179', 't', '4901', 'i', '6197', '2809', 'e', 's', 'j', '4261', 'f', '6649', '7527', '3839', '5651', '9287', 'n', '2505', 's', 'q', '2825', 'g']

Ex Output:
b, d, e, f, g, i, j, k, m, n, q, r, s, t, x


Ex Input:
['i', 'h', '9207', 'j', '5561', '7573', '8879', 'o', 's', '5541', 'i', 'b', '6565', 'i', 'v', '6817', '4965']

Ex Output:

b, h, i, j, o, s, v