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:
['o', '1217', '449', 'n', 'e', 'o', 't', '9043', '1925', '5687', '7197', '7943', 'u', '5053', 'q', 'e', '89', 'l', 'h', '3083', '4295', 'o', 'n', '6309', '743', 'n', 'j', '2105', 's', '6845', 'p', 'p', '1355', '3757', 'v', 'f', '961', '4623', '4633', 'p', '4593', 'p', '7337', 'o', 'u']
answer:
e, f, h, j, l, n, o, p, q, s, t, u, v


question:
['907', '2407', '1385', '3593', 'x', '4143', '2271', '8361', 'q', '5093', 'd', '257', 'm', 'a', '5751', '7845', '3925', '3517', '7753', 'e', '5803', '2629', 't', 'e', '845', '6157', '9787', '225', 'j', 'j', 'l', '1321', 'k', '2459', 'u', '9113', '3193', 'a', 'j', 't']
answer:
a, d, e, j, k, l, m, q, t, u, x


question:
['f', 'z', 'k', '5123', '3175', 'i', 'h', 'l', 'o', 'l', 'l', '6941', '2391', '5315', '7965', '481', '8957', '3603', '2551', 'i', 'w', '925', 'l', '3735', '7379', 'n', '9593', '3009', 'k', 'h', 'v', '3559']
answer:

f, h, i, k, l, n, o, v, w, z