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: ['2381', '2865', '4821', 'n', 'u', 's', 'p', 'v', 'v', 'n', '1349', '7903', 'm', '193', 't', 'p', 'c', '3521', 'a', 't', '8281', 'i', '151', '4783', 'm', '3387', '9551', 'z', 'q', 'v', '4549', '4411', 'u', '8735', '2645', '359', '2871', '5923', '5071', 'c', '9843', 'i']

Answer: a, c, i, m, n, p, q, s, t, u, v, z


Question: ['2393', 'c', '4413', '5529', '1487', '2499', 'i', 's', 'i', '8575', 'm', 'z', '7179', '6637', '9181', 'z', 'h', '2487', 'i', '3779', '2017', '5217', '5013']

Answer: c, h, i, m, s, z


Question: ['j', 'g', 't', 'i', 'o', '7677', '7165', 'g', 'q', '5435', 'w', '7977', '8063', '883', '7097', '3557', '6357', '7899', '7341', '5111', 'u', '9707']

Answer:
g, i, j, o, q, t, u, w