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:
['4397', '2685', '9539', '4343', '6697', '7693', 'g', 'c', '3587', '4691', 'j', '8931', '7397', '2103', '3431', 'u', 'l', 's', 'v', 'q', 'd', '1289', 'h', '1695', 'h', 'j', 'e', '1225', 'e', '7893', 'o', 'i', '3351']

Ex Output:
c, d, e, g, h, i, j, l, o, q, s, u, v


Ex Input:
['1649', 'l', 'i', '5901', 'o', 'g', '1197', 'a', '9327', '9835', '1095', 'k', '4489', '9149', 'o', '3095', 'z', 'u', 'y', '561', '7419', 't', 'j', '8763', 'v', '339', 'y', 'w', 'v', 'v', '1867', 'd', 'r', 'w', 'h', 'j', '1531', '3841']

Ex Output:
a, d, g, h, i, j, k, l, o, r, t, u, v, w, y, z


Ex Input:
['3815', '9817', '8055', 'o', '8325', 'y', 'u', '1159', 'c', '567', 'd', 'x', '3005', 'b', '5501', 'c', 'r', '6359', 'v', '953', 'j', '5699', '4267', 'e', 'c', 'm', 'o', 'v', 'a', 'p', '9349', '15', '9609', 'j', 'e', '1733', '8131', 'i', '9171', 'c', 'p']

Ex Output:

a, b, c, d, e, i, j, m, o, p, r, u, v, x, y