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]: ['8815', 'w', '8629', 'y', '3891']
[EX A]: w, y

[EX Q]: ['h', 'u', 'y', '7677', '9441', '1769', 'v', '1433', 'l', '7739', 'a', '8305', 'n', 'a', '6711', '3161', 'e', 'u', '993', '2211', '4011', 'q', 'o']
[EX A]: a, e, h, l, n, o, q, u, v, y

[EX Q]: ['8355', 'k', 'd', '4729', '6905', '6297', '7599', 't', '289', 'o', 'o', 'n', '8401', '8365', '9613', '8813', 'i', 't', '7277', 'v', 'k', 'u', '4735', 'u', '903', 'r', 'x', '4027', 'r', 'v', 'b', '9811', '6841', 'i', '9589', 'h', 'o', '5981', '8463', '5019', '6793', '4201', '1153']
[EX A]:
b, d, h, i, k, n, o, r, t, u, v, x