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.
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Question: ['9833', '3383', 'h', '3545', '2899', 'y', 'p', 'q', '1901', '3317', '5641', 'v', 'c', 'u', '5521', 'e', '7997', '2439', '5573', '4119', 'k', '8291', '1009', '8253', '405', '233', 'p']

Answer: c, e, h, k, p, q, u, v, y


Question: ['2633', 'd', 'r', '8083', 'f', 'd', '5121', '8651', 'o', 'b', '811', '7551', 'x', 'p', 'm', 'v', 'm', '7833', '1959', 'y', 'p', '779', '1889']

Answer: b, d, f, m, o, p, r, v, x, y


Question: ['3911', 'f', '8341', '6909', '9075', '7431', 'i', 'e', 'o', '2727', 'x', '6381', 'a', '2635', 'e', 's', 'j', '8841', '5649', '1319', '4633', 'g', '4357', 'h', '4559', 'w', '1895', '1821', '633', '8029', 'o', 'q', '1307', '101', '5401', 'q', 'j', '765', '8531']

Answer:
a, e, f, g, h, i, j, o, q, s, w, x