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: ['135', 'u', '3435', '2985', '9811', 'y', '4309', '9757', '905', 'd', 'g', 'q', '1457', 'l', 'o', 'u', '4517', '2333', '3327', '577', 'a', '4041', '8101', '6211', 'f', 'j', '1721', '7217', 'q', '7443', '8477', '3117', '7779', '9339', '8615', 'm', 'c', 'f', 'c', '8979', '7895', 'k', 'w', '1619']

Answer: a, c, d, f, g, j, k, l, m, o, q, u, w, y


Question: ['3995', 'n', 'z', '8389', '7857', '3005', 'i', 'e', '1117', 'z', '8251', 'r', 't']

Answer: e, i, n, r, t, z


Question: ['v', '3327', '2071', '269', 'y', 'n', 't', '9569', 'n', '1645', '1601', 'm', '5661', '5759', '4029', '375', '5881', '9243', '7367', 'r', 'y', '6881', '705', 'o', 'n', '2227', 'x', 'y', 'w', 'c', 'a', '833', 'w', '717', 'n', 'p', '5853', '7063', '6847', 'q', 'a', '737', 'h', '9647', '203']

Answer:
a, c, h, m, n, o, p, q, r, t, v, w, x, y