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]: ['747', '5385', '5313', 'p', '9581', 'r', '1339', '3919', 'e', 'e', '8057', '7739', 'i', 'e', '3311', '963', 'g', 'h', '7349', 'y', '1493', 'e', '3055']
[EX A]: e, g, h, i, p, r, y

[EX Q]: ['2381', '2865', '4821', 'n', 'u', 's', 'p', 'v', 'v', 'n', '1349', '7903', 'm', '193', 't', 'p', 'c', '3521', 'a', 't', '8281', 'i', '151', '4783', 'm', '3387', '9551', 'z', 'q', 'v', '4549', '4411', 'u', '8735', '2645', '359', '2871', '5923', '5071', 'c', '9843', 'i']
[EX A]: a, c, i, m, n, p, q, s, t, u, v, z

[EX Q]: ['6781', '8447', 'q', '7855', '8101', '9243', 'e', 'a', '3723', 'd', '3243', 'u', 'n', '1557', '9573', 'l', 'o', 'h', 'v', '4017', 'u', '6085', 'r', 'l', 's', 'u', 'g', 'l', '5109', '7443', 'n', '9061']
[EX A]:
a, d, e, g, h, l, n, o, q, r, s, u, v