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: ['n', '7337', '6887', '2203', '4663', '2837', '6451', '959', '8027', 'p', 'v', 'q', 'g', '8059', '6151', 'v', '7097', '6583', '7637', '2367', 'w', '9603', '5365', '3773', '1707', 'k', 'x', 's', 'c', 'u', '3641', '6137', '1207', 'k', '5531', '4543']

A: c, g, k, n, p, q, s, u, v, w, x
****
Q: ['2819', 'k', 'u', 'a', '4575', 'a', 't', 'a', 'f', '1507', '415', 'w', 'o', 'o']

A: a, f, k, o, t, u, w
****
Q: ['5635', 'c', '7943', 'u', 'x', '8547', 'l', 'd', 'g', '6691', 'p', '7547', '6007', 'q', 'r', '1269', '4441', '2267', '4685', '4849', 'r', 'j', 'i', '9519', 'y', 't', 'm', 'x', 'a', '3259', 'w', 'h', '5201', 'x', '41', 'n', 'l', 'r', '8481']

A:
a, c, d, g, h, i, j, l, m, n, p, q, r, t, u, w, x, y
****