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: ['q', 'o', '1205', '4429', '6301', 'e', '2857', '5075', '5121', 'p', 'b', '5801', 'a', 'm', 'j', 'p', '1279', '7011', 'x', '2557', 'k', 'v', 'b', 'u', 'w', 'n', '1689', 'o', '1583', 'w', '6403', 'p', '6397', 'e', '823', '5699', 'd', '3399', 'd', 'b']

Answer: a, b, d, e, j, k, m, n, o, p, q, u, v, w, x


Question: ['1749', 'i', 'w', 'j', '3171', '1999', '1037', '4937', '7013', '3593', '287', 'o', 'i', 'j']

Answer: i, j, o, w


Question: ['f', '461', '7897', 'b', '1093', 'j', '6191', 'u', '1875', 'z', 'k', 'k', 'n', 'y', '8605', 'e']

Answer:
b, e, f, j, k, n, u, y, z