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]: ['u', '8229', '2731', '6595', '4675', 'n', 'a', '7361', '7401', '7273', 'b', '279', '5539', '7919', 'j', 'x', '9521', '8837', '7391', 'h', 'x', 'h', '7283', 't', '3769', '2317', '9131', 'h', 'y', 'c', '1625', 'm', 'e', 'a', '8437', '7543', 'p', '2451', 'k', 'r']
[EX A]: a, b, c, e, h, j, k, m, n, p, r, t, u, x, y

[EX Q]: ['2313', '2073', 'd', 'e', 'o', '793', '4999', 'f', 'c', '4473', '4519', 'u', 'n', 'k', '69', '475', 'a', 'j', 'q', 'x', '5869', '9523', 'z', 'v', '9265', '5989', 'p', 'm', 'g', 'y', 'b']
[EX A]: a, b, c, d, e, f, g, j, k, m, n, o, p, q, u, v, x, y, z

[EX Q]: ['c', '5647', '4271', '9479', 'l', '1065', '9351', 'p', 'o', 't', 'n', 's', 'i', 'v', '191', 'p', '4613', 'q', 'g', 'z', 'u', '1477', '1269', 'i', 'g', 'r', '747', 'w', 'a', 'r', '5491']
[EX A]:
a, c, g, i, l, n, o, p, q, r, s, t, u, v, w, z