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:
['f', 'w', 'y', 't', '5269', '9989', 'p', 'v', '6609', 'v', 'c', 'q', 'm', '6565', '189', 'm', '3617', 'b', '9147', '665', 'v', '5989', '1511', '3123', '6667', '4661', '185', 'b', '3405', 'b', '6027', 'n', '6973', '505', 'g', '815', '3439', '2069', '291', 'j', 'f', '1121', '8009', 'm', '8353']

Ex Output:
b, c, f, g, j, m, n, p, q, t, v, w, y


Ex Input:
['6599', 'f', 'c', '661', 'q', 'e', '1951', 'f', 'f', 'a', 'd', '9521', '853', 'n', 'w', '6451', '5549', 'k', 't', 'l', 'z', 'm', 'k', '567']

Ex Output:
a, c, d, e, f, k, l, m, n, q, t, w, z


Ex Input:
['6599', '7821', '3415', '5751', '995', 'l', 'a', 's', '5443', '2513', '4807', '6311', '8919', 'n', 'd', 'q', 'o', '3773', 'h', 'a', '5429', '8077', 'y', 'x', 'w', 'h', 'b', '3105', '8509', '3897', 't', '9705', 'y', '4899']

Ex Output:

a, b, d, h, l, n, o, q, s, t, w, x, y