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:
['m', 'z', 'd', '4667', 'v', '2881', '887', 's', '9861', 'd', '8821', '125', 't', '4493', '6749', '2983', '309', '6033', 'i', '3421', 'j', '4001']
answer:
d, i, j, m, s, t, v, z


question:
['n', '9571', '2983', '7597', 'v', 'y', '1993', '1403', '8309', '7043', 'c', '7329', 'p', '4479', 'p']
answer:
c, n, p, v, y


question:
['2935', '9563', '4411', '6045', 'd', '4963', 'h', 'l', '893', '1655', 'c', '2295', '6185', 'd', 'h']
answer:

c, d, h, l