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.

[Q]: ['1063', 'f', 'm', 'i', 'x', 'i', 'd']
[A]: d, f, i, m, x


[Q]: ['e', '1251', 'y', '6689', '6389', 'h', 't', '503', '5093', 'e', '923', '7051', 'm', 'u', '4501', '3289', '6887', '8341', 'o', '3671', 'n', 'w', '7749', 's', 'j', 'o', '8429', 'q', 'v', 'p', 'd', 'g', 'i', 'f']
[A]: d, e, f, g, h, i, j, m, n, o, p, q, s, t, u, v, w, y


[Q]: ['9639', 'w', 'm', '3287', '4641', 'l', '8379', '6983', 'k', '4963', '8133', 'g', 'y', '2787', '3671', '2129', '9217', '5633', '981', '255', '1871', '4925', 'd', '3749', '9573']
[A]:
d, g, k, l, m, w, y