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]: ['r', 's', '3409', 'a', 'e', '6855', 'i', 'n', '8655', 's', 't', '8401', 'u', '9603', '8815', 'q', 'a', 'x', 'i', '8455', 'e', '5877', '3917', 'p']
[A]: a, e, i, n, p, q, r, s, t, u, x


[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']
[A]: a, b, e, h, i, j, k, n, s, u, v, w, y


[Q]: ['z', 't', '9371', 'b', 't', '8551', '3133', 'l', '4367', 'c', 'l', '407', '7485', '3011', 'y', '2045']
[A]:
b, c, l, t, y, z