Detailed Instructions: 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.
Q: ['g', 'i', 'u', 'd', '6559', 'n', '7421', '4363', '8711', '903', 'a', 'j', 'a', '303', '8609', '1847', 'l', 'x', 'x', 'r', 'i', 'i', '929', 's', 'n', 'r', '3265', '941', '1013', '719', 'a', 'a', 'l', 'j']
A:
a, d, g, i, j, l, n, r, s, u, x