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]: ['j', '917', 'w', 't', '8873', '1431', '8059', '7041']
[A]: j, t, w


[Q]: ['e', 'z', '5199', 'x']
[A]: e, x, z


[Q]: ['6849', 'e', 'v', 'h', '1307', 'c', 'e', 'x', '8459', 'r', 'j', '5285', 'q', 'c', '5049', '3943', 'n', '7133', '9011', 'u', 'l', '1461', '2309', '3671', 'i', '7519']
[A]:
c, e, h, i, j, l, n, q, r, u, v, x