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:
['w', '5341', 'b', '6243', 'v', '877', '1087', '6763', '5241', '3369', '9119', 't', 'v', 'j', '8261', 'o', 'b']

Ex Output:
b, j, o, t, v, w


Ex Input:
['2381', 'y', '6631', '5839', 'r', 'm', 'z', 'b', '4663', '595', '7771', '5305', '5087', '3317', '3125', '9551', '4343', '5121', 'm', 'i', '131', '8401', '5379', '1775', 'u', '1125', '9793', '4123', 'h', '1613']

Ex Output:
b, h, i, m, r, u, y, z


Ex Input:
['9', '517', 'z', 'j', '7821', 'u', 'n', '4609', '7425', '7851', 'e', 'v', 'j', '9739']

Ex Output:

e, j, n, u, v, z