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: ['2173', '1475', '8625', 'e', '1337', 'c', 'o', 'e', '6217', 'h', '3197', '5927', 'd', '4013', '2439', 'z', '5987', 'k', '1693', 'b', 'm', '2625', '7471', 'x', 'i', 'x', '2179', 'v', '8057', '7129', 'g', 't']
A:
b, c, d, e, g, h, i, k, m, o, t, v, x, z