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: ['9425', 'l', 'c', 'n', '5925', '2543', '3935', 'c', '7533', 'j', 'q', '3775', '5897', '9435', '69', 'e']

Answer: c, e, j, l, n, q


Question: ['1653', '3177', 'b', '2785', '2515', 'd', '5513', '5599', '2947', 'v', '2771', '5697', '2913', '4161', '5939', '2655', '6787', '9851', 'q', '3199', 'x', '1305', '9423', '9117', '4821', 'j', '7963', 'i', 's', '469', 'r', 'w']

Answer: b, d, i, j, q, r, s, v, w, x


Question: ['6569', '2977', 's', 'j', 'p', 'q', '5289', 'w', 'u', '7307', '4587', 'o', 's', 'o', '5983', 'u', '3763', 'y', '753', '1673', '3359', 'e', '4797', 'q', '7333', '3747', 'k', '9901', 'y', '6355', '2387', '519', 'r', '3457', '5869', '9779', '3301', '281', 'i']

Answer:
e, i, j, k, o, p, q, r, s, u, w, y