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]: ['j', '8797', 'i', '5443', 'i', 'f', '7593', 'u', 'h', '3251', 'l', '681', 'y', 'n', 'r', '1699', '1379', '8987', '6955', 'x', 'p', 'x', '553', 'q', '5679', 'q', 'w', '9007', 'r', '8945', '7351', 'a', 'v', 'k', '1309', 'v', 'i', '4161', 'a', 'q', '2919', '6917', '6845']
[EX A]: a, f, h, i, j, k, l, n, p, q, r, u, v, w, x, y

[EX Q]: ['5499', 'v', '6507', 'w', 'c', '8431', '8861', '5391', '4765', '4295', '1865', '485', '7255', '1205', 'p', 'w', 'q', '6833', '959', 'a', 'i', '2599', '7779', 'h', '9651', 'g', 'r', 'e', 'u', '4511', '1587', '5601', '8287', '5685', 'u', 'g', '2853', 'p', 'k']
[EX A]: a, c, e, g, h, i, k, p, q, r, u, v, w

[EX Q]: ['3439', '8331', 'n', '5107', 'b', 'o', 'y', '8371', '965', 'p', 'j', 'g', '8073', 'l', 'y', '7327', '5211', '4897', 'i', '1375', '2007', '863', 's', '8489', '831', 'y', '1803', 'd', 'r', 'j', 'r', 'h', 'z', '5743', '9865', 'a', '2929', '5097', 'p', '4193', '7033', '4507', 't', '3323']
[EX A]:
a, b, d, g, h, i, j, l, n, o, p, r, s, t, y, z