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

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


Question: ['2247', 'w', 'h', '4675', '6153', 'f', '6029', 'o', 'd', 'j', 'z', 'y', 'i', '6899', '3917', 'u', '6447', '6405', 'a', '1705', '8585', 'v', 'f', 'r']

Answer: a, d, f, h, i, j, o, r, u, v, w, y, z


Question: ['y', '7813', 'u', 'i', 'k', 'd', '4401', 's', '7627', 'j', '7785', '7349', '1591', 'q', 'j', 's', '7703', 'v', 'h', '6351', '4581', 'u', '881']

Answer:
d, h, i, j, k, q, s, u, v, y