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: ['789', '3603', '3517', '5831', 'z', 'q', 'w', 'l', '5701', '9503', '8169', '1123', 'e', '529', 'j', 'z', 'l', 'o', '3705', 'o', '5131', '6063', 'c', 'j', '6275', '7701']

Answer: c, e, j, l, o, q, w, z


Question: ['5611', 'x', 't', 'p', '5711', '7079', '5251', '429', 'z', 'u', '8721', '9321', '79', 'i', '189', '3605', 'k', '445', 'r', 'k', 'o', '2189', '8521', '8849', '2651', 'm', '4149', '1577', '3085', '5275', '6413', '5265', '6089', 'r', 'f', '5013']

Answer: f, i, k, m, o, p, r, t, u, x, z


Question: ['8887', 'q', 'c', 'q', '6629', '1321', '8083', '6689', '17', 's', 'l', 'r', 'o', '8997', '6987', '4859', 'i', 'o', 's', 'u', '7107', 't', 'g', 'y', '7753', '3591', '1097', '3639', 'r', '6821', '7447', 'y', 'k', 'v', 'z']

Answer:
c, g, i, k, l, o, q, r, s, t, u, v, y, z