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:
['3307', 'r', '2665', '3453', 'f', 'd', 'v', '3801', '3153', '3137', 'y', 'i', '9681', 'k', '9253', 'y', 'i', '8631', '2375', '5131', 'r', 'z', '8645', '595', 's', '6749', '2665', '709', '8203']
answer:
d, f, i, k, r, s, v, y, z


question:
['6143', '9073', 'h', '1459', 'q', '5799', '6555', '525', '7921', '5041', '3273', '383', 'd', '9075']
answer:
d, h, q


question:
['l', '455', '9645', 'x', 'v', 'o', '6303', '8187', '3447', 'm', 'o', 'v', 'e', '669', 'x', '7657', '417']
answer:

e, l, m, o, v, x