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:
['5611', 'x', 't', 'p', '5711', '7079', '5251', '429', 'z', 'u', '8721', '9321', '79', 'i', '189', '3605', 'k', '445', 'r', 'k', 'o', '2189', '8521', '8849', '2651', 'm', '4149', '1577', '3085', '5275', '6413', '5265', '6089', 'r', 'f', '5013']

Ex Output:
f, i, k, m, o, p, r, t, u, x, z


Ex Input:
['5971', 'x', 'c']

Ex Output:
c, x


Ex Input:
['k', 's', 'k', '4375', 'q', 'e', '5607', '5845', 'd', '1025', '1111', 'o', 'd', '6493', 'i', 'r', '6757', 'u', '9179', '4493', 'y', 'x', '1885']

Ex Output:

d, e, i, k, o, q, r, s, u, x, y