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:
['d', '1989', '6365', 'y', 'm', '1245', '7539', 'm', '3787', '6987', 'e', 'e', 'y', '9577', 'b', '5', '8179', 'x', '2853', '6337', 'w', 'f', 'b', 'q', '563', '6077', '1133', 'x', '6045']

Ex Output:
b, d, e, f, m, q, w, x, y


Ex Input:
['2329', 'i']

Ex Output:
i


Ex Input:
['3829', 'w', '6723', 'i', '7281', 'q', 'a', 'i', '6599', '9517', '1375', 'm', 'j', '1931', '4209', '4813', 'h', '6231', 'x', 't', '4583', 'e', 'v', 'n', '5031', '7215', 'z', '9269', 'i', '721', 'm', '6579', '1965', 'z', '2331', '9227', 'c']

Ex Output:

a, c, e, h, i, j, m, n, q, t, v, w, x, z