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]: ['k', '8917', '3773', '6723', 'r', 'z', '3265', 'o', 'f', 'q', '9343', 'f', '1925', 'u', 'b', 'o', '5275', 'b', 'n', 'd', 'j', '4825']
[A]: b, d, f, j, k, n, o, q, r, u, z


[Q]: ['e', '2239', 'l', '8309', 'i', '2613', 'i', '611', '6481', 'j', 'v', '1867', '415', '269', '8053', '3369', 'q', 't', '2303', '7729', '1059', '6135', '3299', 'd', '6855', '207', '6227', '7859']
[A]: d, e, i, j, l, q, t, v


[Q]: ['985', 'g', '2493', '1911', '1717', 'g', '3565', 'x', '723', '9539', 'l', '8445', '4001', '8719', '1017', 'o', '3965', 'y', '1157', 'f', 'j', 'b', 'u', '1981']
[A]:
b, f, g, j, l, o, u, x, y