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:
['5433', '4011', '2113', '2299', 'e', '9829', 'd', 'q', 'e', '3921', 'a', 'q', '8953', 'q', 'g', 'w', 'z', 'u', '4425', 'b', 'q', '5315', 'b', 'u', 'h', 'y', '9733', 'b', 'c', '1225', 'a']

Ex Output:
a, b, c, d, e, g, h, q, u, w, y, z


Ex Input:
['333', 'b', '261', 'k', 'p', '7861']

Ex Output:
b, k, p


Ex Input:
['4323', '9027', '3191', 'k', 'k', 'f', '1535', '3883', 'd', 'j', '7717', '4829', 'v', 'z', 'q', '1621', 't', '2777', '9091', 'a', '7307', 'w', 'n', '7591', 'f', 'l', 'e', 't', 'q', 'r', '5143', '9791', '121', 'g', 'y', '6567', 'u', 'l', '1749']

Ex Output:

a, d, e, f, g, j, k, l, n, q, r, t, u, v, w, y, z