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: ['2349', 'p', 'a', '435', 'y', 'h', '3249', 'o']

Answer: a, h, o, p, y


Question: ['k', '1995', 'b', '2581', 'x', '2639', 'i', '6761', '2701', 'd', '6993', '9375', 'r', 'm', '249', '8115', '8179', 't', '4901', 'i', '6197', '2809', 'e', 's', 'j', '4261', 'f', '6649', '7527', '3839', '5651', '9287', 'n', '2505', 's', 'q', '2825', 'g']

Answer: b, d, e, f, g, i, j, k, m, n, q, r, s, t, x


Question: ['461', '8839', '3825', 'e', '4913', 's', 'v', '4963', 's', 'g', 'e', 'z', '3549', 'b', '2399', '3623', 'v', 'f', 'c', 'a', '6125', '5165', '7779', '9097', '7653', 'y']

Answer:
a, b, c, e, f, g, s, v, y, z