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: ['n', 'h', 'h', 'e', 'p', '1265', '4853', '9433', '1227', '1619', '6381', 'o', '8285', 'k', 'u', '7471', 'm', '6887', '6579', '5813', '5563', '8535', 'n', '3743', 'h', 't', '4497', '2791', 'e', 'v', '6769', '7969', 'x', 't', 'x', 'q']

Answer: e, h, k, m, n, o, p, q, t, u, v, x


Question: ['t', 'c', 'r', '4459', 'o', '1407', 'x', '1515', '331', 'm', '1535', 'p', 'u', 'g', '2513', 'o', '7827', '8149', 'd', 'z', 'q', '5655', 'x', '9997', '2809', 'g', 'h', '6309', 'a', 'j', '9773', '2115', 't', '9113', 'q', 'o', '427', 's', '3815', '5423', 's', 'n', 'i', 'o', '3643']

Answer: a, c, d, g, h, i, j, m, n, o, p, q, r, s, t, u, x, z


Question: ['6481', 'z', 'i', '6539', '3071', '4439', '9847', '6413', 'r', '6963', 'n', '229', '4989', '7393', 'r', '9655', 'a', '8239', 'm', '3363', '3255', 'u', 'a', 'y', 'o', 'y', 'm', 'e', 'k', 'v', '9413', 'a', '6035']

Answer:
a, e, i, k, m, n, o, r, u, v, y, z