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]: ['p', 'p', '7899', 'u', '971', '7289', 't', '5217', 'k', 'z', 'y', 'y', '6905', '9499', '4085', 'x', '955', 'v', 'j', '9049', '7927', '1757', '193', '2181']
[EX A]: j, k, p, t, u, v, x, y, z

[EX Q]: ['5463', '5683', 'w', '4071', '3997', 'i', '9677', 'q', 'l', 'v', 'w', '5325', '197', 'g', 'g', '3227', '3477']
[EX A]: g, i, l, q, v, w

[EX Q]: ['o', 'i', 'z', '9481', '4861', '6381', 'm', '2689', 's', '7145', 'z', 'n', 'v', 'p', 'g', 'k', 'h', '825', '7989', '7089', 'o', 'v', '5141', 'u', 'k', '9559', 'h', 'r', '5169', 'x', 'n', 'l', 't', '3309', 'e', '8473']
[EX A]:
e, g, h, i, k, l, m, n, o, p, r, s, t, u, v, x, z