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.
--------
Question: ['4269', '1847', '2025', '601', 'g', 'n', 'h', '3499', '4977', '3579', '9355', '3489', 'm', 'm', '4401', '4605', 'l', '3977', 'h', 'd', 't', '5135', '7787', 'k', 'q', '7699', '5325', '6269', '1865', 'h', '8915', '5677', 'g', '603', '1435']

Answer: d, g, h, k, l, m, n, q, t


Question: ['e', 'k', '7569', '6387', '4593', '2445', '345', '2905', 'h', '3119', '7001', 'x', 'a', '2943', '3635', 'l', 'q', 'z', 'g', '2657', '7849', 'i', '9413', 'm', 'e', '2951', 'd', '2963', 'b', 'u', 't', 'i', '1141', 'c', 'm', '8607', 's']

Answer: a, b, c, d, e, g, h, i, k, l, m, q, s, t, u, x, z


Question: ['u', '7373', '3515', 'x', '1087', '3723', 'f', '867', 'b', 'v', '3039', '8027', 'n', '7691', '5317', '3777', 'c', 'b', 'i', '3897', '3637', 'n', 'r', '7023', 'z', '7993', 'n', '8569', 'k', '3441', '8705', '227', '8949', 'h', 'e', '1449', 'z', 't', 'y', 'n', '3923', 'u', '1023']

Answer:
b, c, e, f, h, i, k, n, r, t, u, v, x, y, z