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: ['z', '2519', '4799', '4715', '7165', 'r', 'r', 'l', 'n', '6925', '8935', '9795', '5489', 'v', 'u', '6527', '2241', 'u', 'c', 'w', '9755', 'w', '9823', 'g']

Answer: c, g, l, n, r, u, v, w, z


Question: ['n', '6615', 'r', 'q', '3803', '4641', '9775', '7719', 'n', '6571', '2723', '6919', 'e', 'f', '1919', '6963', '2581', 'y', '713', 'w', 'w', 'w', 'l', 's', '3993', '9563', '9365', '9277', '103', '2737', 'y', '6005', '9763', 'p', '261']

Answer: e, f, l, n, p, q, r, s, w, y


Question: ['2645', '6153', '2279', '8639', '377', 's', 'k', 'x', 'p', '1133', 'd', 'x', '6825', 'g', 'p', 'f', 'n', 'y', '9989', '8813', '2127', 'k', '8321', 'g', '5339', 'q', 'o', 'n', '8295', '7067', '9179']

Answer:
d, f, g, k, n, o, p, q, s, x, y