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.

[EX Q]: ['5973', 'h', '4081', 'i', '8059', 'w', 'j', '6175', 'w', '8685', '5811', 'k', 'n', '5577', '9817', 'v', '8617', 'u', 'y', '3921', 'b', '1027', '5405', 'a', '3501', '6659', 's', 'e', '157']
[EX A]: a, b, e, h, i, j, k, n, s, u, v, w, y

[EX Q]: ['o', 'c', '6469', 'x', '8815', '4441', '6193', 'u', 'm', 'a', '9879', 'p', '8335', 'c', 'z']
[EX A]: a, c, m, o, p, u, x, z

[EX Q]: ['t', 'd', '6635', 'i', 'm', 'q', 't', 'z', '2765', 'j', '9129', '8787', '7551', 'p', 'o', 'v', 'r', '2493', '9035', '9895', 'v', 'a', 'w', 'j', 'j', '5347']
[EX A]:
a, d, i, j, m, o, p, q, r, t, v, w, z