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: ['w', 'o', 'l', '1857', 's', 'q', 'j', 'e', '5945', 'g', 'l', '9563', 'e', 'u', '7633', '7977', '4943', 'y', '5621', 'f', '1653', 'c', 'l', '2843', '2125', '7731', '5257', '5667', 'b', 'b', '5765', 'a', 't', '8163', '9785', '5385']

Answer: a, b, c, e, f, g, j, l, o, q, s, t, u, w, y


Question: ['r', '4655', 'm', 'l', '4371', 'o', '5331', '5469', 'j', 'u', '4915', 'v', 'i', 'f', 'j', '6139', 'y', '2423', '1271', '2289', '5565', '7561', '9697', 'e', 's', 'u', '9581', 'y', '6095', '5047', '625', '9047', 'd', 's', '8307', '3615', '8145']

Answer: d, e, f, i, j, l, m, o, r, s, u, v, y


Question: ['2671', 'u', 'u', 's', 'j', 'p', 'i', '5467', '8131', 'x', '4341', '4707', 'r', 'm', '3831', '451', 'w', '5509', 'v']

Answer:
i, j, m, p, r, s, u, v, w, x