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', 'r', '7769', '2159', 's', '3269', '5527', 'l', 'z', 'e', '5165', 'x', 'x', '8273', 'g', 'm', '7609', '4015', '6403', '3753', 'y', 'h', 'l', 'i', '389', 'm', 'u', '6845', 'r', 'c', '7571', '3355', '9755', 'n', '4625', 'p', '5645', '1703', '4439', 't', '8431']

Answer: c, d, e, g, h, i, l, m, n, p, r, s, t, u, x, y, z


Question: ['5489', 'f', '6833', 's', 'c', '6575', 'w', '2957', '8465', 'v', 'h', '2119', '7731', 'e', '5367', 'e', '3357', 'p', '7565', 'n', 'x', 'n', 'f', '1075', '5941', '6505', 'j', 'p', '2853', 'l', 'q', '4727', 's']

Answer: c, e, f, h, j, l, n, p, q, s, v, w, x


Question: ['8315', '8319', 'w', '8575', 'n', 'x', '4481', 'l', 'g', 'p', '2891', 'i', '2681', 'j', '6795', '399', 'z', 'i', '3471', '2845', 'y', 'r', '2437', 'c', 'l', '4191', '6633', 'f', '3719', 'p', 'z', '9589', '5011', 'w', 'c', '8987', 'r', 'n', '3597', '4837', '4255', '4751']

Answer:
c, f, g, i, j, l, n, p, r, w, x, y, z