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]: ['5337', '4877', '9443', '3445', 'u', '2571', 't', 'n', 'x', '1985', '5145', '3397', 'p', '9259', 's', 'x', 'u', 'c', 'g', 't', 'j', '829', '8273', 'e', 'j', 'r', 'x', '865', '4773', 'h', '4407', '8591']
[EX A]: c, e, g, h, j, n, p, r, s, t, u, x

[EX Q]: ['i', 'h', '8299', 'e', 'c', '5543', '5241', 'f', '3985', 'f', 'z', '1245', 'e', 't', 'g', '5199', '9217', 'q', 'j', 'p', '767', 'z', '1803', 'k', '7303', '3187', '2507', '6471', '3337', '6037', '9291', 'a', 'l']
[EX A]: a, c, e, f, g, h, i, j, k, l, p, q, t, z

[EX Q]: ['w', '3395', 'p', 'b', 'e', '8595', '2591', 'u', '8831', 'l', '5063', '5843', 's']
[EX A]:
b, e, l, p, s, u, w