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:
['l', '1213', 'm', 'k', '7825', '3501', '2397', '2313', 'v', '4119', 'h', 't', '6137', 'l', '9851', 'q', '9661', 'b', 'z', '1437', '1759', 'l', '611', '5085', '4443', 'n', 'u', 'b', '2511', '6023', '7157', 'n', '9921', 'o', 'a', 'o', 'w', 't', 'o', '1607', '6751', 'n', 'b']
answer:
a, b, h, k, l, m, n, o, q, t, u, v, w, z


question:
['e', '8391', '7065', '6141', '3335', 't', 'i', 'c', '1791', '6333', 'b', 'z', '1621', 'e', 'h', 'u', 'o', 'q', '3195', '6507', '3253', 'c', '2067', '3917', '7111', 'r', 'j', 'd', '3987', '9139', 'm', '981', 'l', 'f', '2417', 'w', '9983', 'h', 'd', '6021', 'a', 'f']
answer:
a, b, c, d, e, f, h, i, j, l, m, o, q, r, t, u, w, z


question:
['t', '8045', 'l', '2599', 'i', '2893', 'h', '1417', '1529', '3553', 'n', 'y', '1425', 'q', '3179', 's', 'n', '1845', 'p', '9469', '6571', '3137', '4031', 'p', 's', 'n', '4323', '507', '4265', '2387', 'l', 'p', 's', 'n', '6351', '6709', 'n', '5463', 'm', '9125', '7243', 'w', 'o', '9049']
answer:

h, i, l, m, n, o, p, q, s, t, w, y