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:
['7065', 'f', 'k', 'i', 'd', '8291', 'z', 'e', 'q', '5345', 'h', '3397', 's', '5355', 's', '9033', 'e', '5241', '5285', 'm', 'h', 'i', 'n', '6471', '3365', 'f', 'r', '6145', 't', '4869']

Ex Output:
d, e, f, h, i, k, m, n, q, r, s, t, z


Ex Input:
['o', 'd', '6495', '5211', '341', 'v', '385', 'v', 'g', 'v', 'l', '7631', '2675', 't']

Ex Output:
d, g, l, o, t, v


Ex Input:
['1963', '2539', 'z', '5439', '6169', 'o', '8551', '3673', '1181', 'r', 'x', '3901', 'u', '5413', 'r', '6979', 'e', 'a', '3937', '4709', 'y', '9627', 'x', '347', '7267', 's', '3127', '4299', '5461', 'i', '6405', '8651', '4759']

Ex Output:

a, e, i, o, r, s, u, x, y, z