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:
['e', '1251', 'y', '6689', '6389', 'h', 't', '503', '5093', 'e', '923', '7051', 'm', 'u', '4501', '3289', '6887', '8341', 'o', '3671', 'n', 'w', '7749', 's', 'j', 'o', '8429', 'q', 'v', 'p', 'd', 'g', 'i', 'f']

Ex Output:
d, e, f, g, h, i, j, m, n, o, p, q, s, t, u, v, w, y


Ex Input:
['7013', '8755', 'u', '9377', 'n', '6997', '507', '8557', '9745', 'g', '3019', '93', 'l', '1219', 'a', '393', '2573', 'q', 'b', '6101', 'e']

Ex Output:
a, b, e, g, l, n, q, u


Ex Input:
['m', '399', 't', 'r', '6473', 't', '271', 'x', '4513', 'w', 'g', '313', 'e', '1327', '1047', 'u', 'x', '7455', 'g', 'r']

Ex Output:

e, g, m, r, t, u, w, x