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: ['1223', 'h', 'a', 'o', 'v', '2535', 'g', '6267', 'w', '9625', '7961', '9577', '7611', '5655', 'p', 'j', 's', '2141', '4101', 'l', '4367', '9383', 'n', '5965', '9097', '7571', 'p', 'u', 'x']

Answer: a, g, h, j, l, n, o, p, s, u, v, w, x


Question: ['7109', '1243', 'f', 'z', 'h', 'd', '6169', 'v', 'h', '3609', '3181', 'd', '3661', '7193', '7341', '9127', 'r', '1623', '5813', 's', 'd', '4011', '4983', 'n', '4195']

Answer: d, f, h, n, r, s, v, z


Question: ['q', '555', '4063', '7915', '9621', '485', 'c', 'e', 'd', '3535', 'x', 's', '347', 'b', '5885', '2829', 'k', 'c', 't', 'v', 'q', 'p', '2959', '8993', 'r', 'o', 'r', 'c', '4405', '61', 'a', 'n', '1391', 'w', '1693', '7241', '8691', '5553', 'd', '995']

Answer:
a, b, c, d, e, k, n, o, p, q, r, s, t, v, w, x