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', '9641', '8515', '1207', 'd', 'j', '6617', '5529', 'g', 'a', 'o', 'f', 'y', '4993', '4643', '6087', 'n', '3177', 'y', '9471', '1229', '8211', '7079']
[EX A]: a, d, f, g, j, n, o, p, y

[EX Q]: ['o', 'h', 'z', 'n', 'e', 'y', 't', '4371', 'm', '1059', '4853', '8529', 'l']
[EX A]: e, h, l, m, n, o, t, y, z

[EX Q]: ['z', 's', '713', '903', '7279', '6425', '8123', 't', '3813', 'a', '8273', 'w', '7767', '3629', '9463', 'n', '9781', 'l', 's', 'n', 'o', 'r', 'w', '3839', 'f', 'g', 'e', '7963', '7193', '9075']
[EX A]:
a, e, f, g, l, n, o, r, s, t, w, z