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:
['a', '533', '67', 'z', 'z', '9283', 'o', 'a', '7045', '1521', 'm', 'h', 'q', '4173', '7497', '319', '5721', '6097', 'i', '9829', '1801', '7347', 'r', 'z', '239', '4279', 'e', 'k', 'r', 'v', '6653', '599', '8597', 'd', 'r']
answer:
a, d, e, h, i, k, m, o, q, r, v, z


question:
['9425', 'l', 'c', 'n', '5925', '2543', '3935', 'c', '7533', 'j', 'q', '3775', '5897', '9435', '69', 'e']
answer:
c, e, j, l, n, q


question:
['2205', '1143', 's', '9673', 'n', '7859', 'w', '1803', 'j', 'v', '8443', 'n', 'e', 'r', '5843', '2359', 'e', '7057', '7325', 'a', '5663', 'n', 'w']
answer:

a, e, j, n, r, s, v, w