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: ['d', 'm', 'k', '3513', '8241', '5541', 'm', 's', '1993', '6163', '2753', 'd', 'b', 'm', 'i', '7647', '8631', '9119', '2165', 'x', '3911', '2769', '1673', '7195', 't', 'w', '5555', 'o', '3265']

Answer: b, d, i, k, m, o, s, t, w, x


Question: ['8281', '4831', '1329', 'g', 'e', '8879', 'n', 's', 'x', 'j', '6305', 'j', '921', '3677', '5107', 'n', 'j', '9285', 'a', '5329', '6671', 'c', '9283', 'l', 'a', '7907', 'q', '7605', '855', '6477']

Answer: a, c, e, g, j, l, n, q, s, x


Question: ['a', 'n', '125', '4967', 'u', 'y', '9263', '9573', 'c', 'a', 'w', '5483', '8163', '2321', '793', 'h', 'w', '9781', '6441', '5113', '4473', '9243', '2971', 'j', 'k', '6691', '5593', '1317', '2809', '1675', '6465', 'x', '7977', 'c', '149', 'c', '1407', '6629', '9947', '3099', 'r', '4583', 'v', '3167']

Answer:
a, c, h, j, k, n, r, u, v, w, x, y