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: ['8357', 'x', 'w', '287', 'z', '2733', '1757', 'w', 'g', '1393', '7201', '4931', 'k', '5185', 'x', '6313', '2255', 'z', 'v', '3593', '6191', '4423', 'm', 'k', '3209', '3559', 'c', 'n', 'm', '5461', '2997', '235', '4045', '6597', 'v', 'e', 'p', 'c', 'k', 'd', '5529', '6241', 'u', 'f', '8067']

Answer: c, d, e, f, g, k, m, n, p, u, v, w, x, z


Question: ['d', '4377', '9271', '8053', '9519']

Answer: d


Question: ['p', 'q', 'd', '801', '7009', '4165', '7801', 's', '5877', 'b', '6833', '4031', 'y', '6309', '9349', 'e', '2817', '5233']

Answer:
b, d, e, p, q, s, y