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:
['2799', '7519', '345', 'e', 'l', '9369', '4703', '4111']

Ex Output:
e, l


Ex Input:
['u', 'k', 'd', '4393', 'u', 'h', 'q', '833', 'k', 'l', '5749', 'r', '7123', '1003', 'z', '531', 'o', 'u', '6601', '6975', '4905', 'n', 'e']

Ex Output:
d, e, h, k, l, n, o, q, r, u, z


Ex Input:
['9823', '5417', 'x', '4283', 'k', 'i', '4931', 'p', '8839', '7283', '2093', '4643', '8227', 'j', 'w', '8025', '8375', '5257', 'h', '4119', 'm']

Ex Output:

h, i, j, k, m, p, w, x