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: ['v', '3765', '4065', 'a', '4201', 'f', 'x', '9275', 'q', '9303']

Answer: a, f, q, v, x


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: ['4525', 'v', '1705', '3449', 'z', 'g', 'r', 'h', 'd', '1489', '1123', 'z', 'r', 'p', '3883', 'r', 'v', '1555', '8761', '4843', '7335', 'q', 'b', 'o', '2975', '9707', 'b', 'i', '2683', '7341', 'k', '9271', 'e', '6303', '9357', '7661', 't']

Answer:
b, d, e, g, h, i, k, o, p, q, r, t, v, z