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: ['5957', 'd', 'i', 'b', 'e', '5565', 'c', 'i', '2919']

Answer: b, c, d, e, i


Question: ['9467', 'o', '8347', '7125', '7999', '1737', 'h', '7043', '8617', '2033', '9959', '2349', 'p', '9389', '5525', 'w', 'u', 'p', '4703', '9807', 's', 'f', '2359', '7357', '2471', '5447', 'f', 'w', '2865', '6627', '3211', 'y', '23', 'z', 's', '1517', '3553', 'r', '2251']

Answer: f, h, o, p, r, s, u, w, y, z


Question: ['6643', 'm', 'r', '2673', 'c', 'n', 'p', 'c', '1705', 'g', '1645', 'd', '5481', 'w', '89', 's', 'h', 'y', '6589', 'n', '2247', 'p', '5085', '1913', '7345', '655', '7625', 'u', 'r', 'x', 'l', '9549', 'q', '3303']

Answer:
c, d, g, h, l, m, n, p, q, r, s, u, w, x, y