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:
['1189', '7143', '993', '1513', '6449', '9749', '5963', '8159', 't', '3543', 'j', 'i', '4227', '1463', '6431', '4987', 'y', 'q', 'f', '321', 'm', 'r']
answer:
f, i, j, m, q, r, t, y


question:
['1653', '3177', 'b', '2785', '2515', 'd', '5513', '5599', '2947', 'v', '2771', '5697', '2913', '4161', '5939', '2655', '6787', '9851', 'q', '3199', 'x', '1305', '9423', '9117', '4821', 'j', '7963', 'i', 's', '469', 'r', 'w']
answer:
b, d, i, j, q, r, s, v, w, x


question:
['6355', '4805']
answer:

-1