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:
['u', 'i', '1185', '3795', '5417', 'k', 'b', '2629', '2635', 'z']

Ex Output:
b, i, k, u, z


Ex Input:
['1197', '305', 's', '1113', 'n', '2207', 'e', '227', '2833', '607', '3049', 'v', '4615', 'a', 'k', 'r', 's', '3571', 'f', '4215', 'f', '8985', '5559', '4111', 'u', '1433', '1943', '8831', 'w', 'x', 'o', '9023', 'u', 'y', 'p', 's', 'h', '8877', 'p', 'n', '8903', '5811']

Ex Output:
a, e, f, h, k, n, o, p, r, s, u, v, w, x, y


Ex Input:
['5011', 'l', '925', 'e', 'b', '3077', 'm', '4541', '781']

Ex Output:

b, e, l, m