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]: ['q', '6421', 'w', 'x', '669', 'h', '3853', '6609', 'p', '947', 'g', 'c', 'x', '2617', 'v', 'e', '4795', '5755', 'a', '2379', 'y', '5939', 'l', 'h', 'g', '3779', 'c', 'm', '3157', '4027', 'g', '2917', '9461', '7271', 't', 'i', '9807', '147']
[EX A]: a, c, e, g, h, i, l, m, p, q, t, v, w, x, y

[EX Q]: ['5089', '6113', 'v', 'l', '5529', 'q', '7499', 'e', 'r', 'c', '5999', '2619', 'a', '2523', '7697', 'j', 'c', '6537', '8313', '5623', '4225', '7677', 'q', 'a', '6559', 'y', 'b', 'm', '7645', '7019', 'r', 'i', '5225', '703', 'i', '6189', 'f', 't', '7553']
[EX A]: a, b, c, e, f, i, j, l, m, q, r, t, v, y

[EX Q]: ['z', '9791', 't', '4691', 'y', '963', '179', 'l', 'x', '4997', '8465', '5089', '431', 'a', 't', '9387', '237', '6455', 'u', '8505', '5719', 'd', '9277', '8027', '2779', 'c', '1067', 'f']
[EX A]:
a, c, d, f, l, t, u, x, y, z