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: ['6655', '7445', '1795', '7495', 'h', 'z', 'u', '2199', 'r', 'p', '2245']

Answer: h, p, r, u, z


Question: ['8739', 'v', 'm', '6277', 'l', 's', '109', '8057', '3835', 'd', 'u', 'f', 'w', 'd', 'p', '7705', '3643', '4455', 'u', 'p', 'u', '9407', 'g', 'w', '595', 'z', '6827', '6879', 'w', 'w', '6973', 'm', 'e', '1553', 'v', '3529', '8953', '3903', '5713', '8249', 'e', '1113', 'b', 't', 'r']

Answer: b, d, e, f, g, l, m, p, r, s, t, u, v, w, z


Question: ['i', '1191', '5581', '2527', 'g', '9795', '519', 'u', '8389', '9793', 'k', '5733', '7125', '7835', 'j', '855', 'd', 'd', '6555', '3211', 'l', 'o', 'b', '523', 'x', 'j', '1707', '4161', '7171', 'h', 'h', 'm', 'h', '2443', 'e', '649', '951', 'n', 'h']

Answer:
b, d, e, g, h, i, j, k, l, m, n, o, u, x