instruction:
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.
question:
['g', '6867', '7965', '3313', 'k', '1827', '7337', 'u', '1209', '5145', 'w', 'h', '9059', 'u', 'b', '3189', '2837', 'k', 'y', 'e', 'b', '4479', '541', '7103', 'h', 'm', '2177', '6377', '3993', '7167', 'q', '2145', '5007', '9135', '5331', 'e']
answer:
b, e, g, h, k, m, q, u, w, y


question:
['9385', '4021', 'y', '9629', 'u', '7623', 'd', '5155', 'x', '2605', '8893', 'l', 'p', 'a', 'm', '6699', 'i', '4503', '6623', 'm', 'l', '6115', 'p', 'w', '9691', '811', '4769', '2659', 'x', 'c', '6513', '5499', 's', 'q', 'f', 'v', 'z', 'w', 'z', '1361']
answer:
a, c, d, f, i, l, m, p, q, s, u, v, w, x, y, z


question:
['2197', 'q', 'g', '9537', '4565', 'r', 'k', 'k', 'e', 'd', 'm', 's', '2725', '9979', 'i', '2051', 'l', '3147', '8747', '1517', '1301', '9657', '5459', '5583', '9583', 'h']
answer:

d, e, g, h, i, k, l, m, q, r, s