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: ['f', 'p', 'n', '839', '9229', 'r', '7661', 'c', '4383', 'u', 'k', '5321', '3181', '1785', 'w', 'k', '8721', '7855', '4093', '6495', 'q', '2467', 'g']

Answer: c, f, g, k, n, p, q, r, u, w


Question: ['f', 'n', '7291', '7373', 'c', 'i', '6295', 'y', 'c', '2537', 'l', 's', '4931', 'v', '4301', 'q', '4769', 'q', '6637', '5527', 't', '4307', 'y', '8665', '4393', '7565', '7155', 'p', '8355', '5733']

Answer:
c, f, i, l, n, p, q, s, t, v, y