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:
['v', '6635', '5395', '3263', '4391', 'h', '1521', 'f', '9861', '6125', '1673', '3679', '8681', '4967', 'f', 'a', 'c', 'k', 'n', '4155', 'e', 'm', 'i', '1699', 'r', 'f', 'u', 'r', '3451', 'v', '7239', 'o', '4359', 'l', 'a', '2925']

Ex Output:
a, c, e, f, h, i, k, l, m, n, o, r, u, v


Ex Input:
['9403', '9881', '8391', 't', '1793', 'w', 'x', 'y', '6383', 'j', 'r', '5323', 'r', 'l', 'e', 'u', '7193', '2309', '837', 'z', 'w', 'n', '4427', '8269', '6333', 'a', 'p', '1933', '8497', '2665', '1349', '6807', '9009', 'b']

Ex Output:
a, b, e, j, l, n, p, r, t, u, w, x, y, z


Ex Input:
['9143', 't', 'n', 'p', 'y', 'd', 'y', '655', 'z', 'r', '1041', 'z', '8039', '9105', '6643', 't', '7303', 'z', 'm', 't', 't', '3121', '7091', 'l', 'w', '4441', '7629', 'h']

Ex Output:

d, h, l, m, n, p, r, t, w, y, z