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:
['h', 'b', '9601', 'h', 'h', 'h', '8099', '8265', 'i', 'd', '8791', 'p', '8059', '4309', '501', '2581', '9837', '157', '4785', '5925', 'q', '8491', '4779', 'r', 'l', 'k', '3679', 'v', 'g', 'g', '9731', '1909', '9783', 'f', '4293', '5009', 'o', '3057', '3157', 'c', '5587', 'b', 'f', 'd', 'k']
answer:
b, c, d, f, g, h, i, k, l, o, p, q, r, v


question:
['8311', 'w', 'f', '3431', '9863', '5817', '3969', '2705', 'x', 'm', 'k', 'z', 'z', '235', 'x', '417', 's', 'i', 'y', '8833', '8675', 's', 'm', '2149', '765', 'u', '1021', '7823', 'x', '7275', '3157', 'k']
answer:
f, i, k, m, s, u, w, x, y, z


question:
['3583', 'd', '1481', 'w', 'l', '7261', '2933', 'n', '8725', 'g', '3441', 'r', '287', '7327', '5637', 'r', '5389', 'm', 'j', 'd', 'a', 'e', 'v', '7879', '1731', 'z', '43', 'q', 'p', '4315', 'p', '3651', 'o', 'l', 's', '9787', 'h', '6735']
answer:

a, d, e, g, h, j, l, m, n, o, p, q, r, s, v, w, z