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]: ['9627', '9879', '5421', '4755', '1533', '6727', 't', '7641', 'd', '3929', 'h', '3989', '8441', 'k', 'p', '2653', 'm', 'b', 'i', '3431', '4907', '5687', 'g', 'h', '9185', '5051', 'k', '7135', '709']
[EX A]: b, d, g, h, i, k, m, p, t

[EX Q]: ['e', 'n', 'y', 'f', 'l', 'h', '455', 'y', '591', 'm', '9041', 'b', 'b', 'o', '4215', '5009', 'o', 'a', '4369', 'u', '6911', '4825', 't', 'k', '6063', '2939']
[EX A]: a, b, e, f, h, k, l, m, n, o, t, u, y

[EX Q]: ['395', 'd', '1971', '7299', '9167', 'g', 'l', '7725', '4539', 't', '9711', 'k', 'a', 'e', '2999', 'i', '9949', 'l', '5003', '8739']
[EX A]:
a, d, e, g, i, k, l, t