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: ['d', '5285', 'z', 't', 'i', '719', 'z', 'b', '3603', '4781', 'o', 'g', 'j', 'd', 'r', 'a', 'x', '5829', '4907', '7395', '993', '2109', '1745', '415', '7525', '1029', '7791', '5321', 'h', '6391', 'g', '4613', '9191', 'o', '7365', '1811', '9695', 'w']

Answer: a, b, d, g, h, i, j, o, r, t, w, x, z


Question: ['q', 'h', 'q', '7185', 'f', 'l', 'r', '3605', 'x', 'i', 'v', '8789', 'u', 'x', 'x', '8315', 'x', 't', 'h', 'o', '4943', '5827', '7677']

Answer: f, h, i, l, o, q, r, t, u, v, x


Question: ['5037', 'c', 'b', 'a', '5931', '6799', 'y', '9291', 'n', 'l', 's', '9457', '2721', 'm', '4193', '5433', 'b', 'z', '6857', 'n', 'v', 'z', '4759', 't', '299', '583', '1789']

Answer:
a, b, c, l, m, n, s, t, v, y, z