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:
['m', '6443', 'd', 'o', 'p', 'q', '3765', 'k', 'm', 'y', 'j', '3531', 'y', 't', '671', 'j', '3699', 'a', 'i', '1843', 't', 'd', '1205', 'k', 'h', '1209', '2913', '1301', 'k', 'd', '1769', '7985', 's', 'p', 'f', '4583']

Ex Output:
a, d, f, h, i, j, k, m, o, p, q, s, t, y


Ex Input:
['8235', 't', '1695', '9899', '3633', 't', '1823', 'r', 'x']

Ex Output:
r, t, x


Ex Input:
['5019', 'i', 'b']

Ex Output:

b, i