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: ['g', '8591', '4463', '2189', '7901', '1457', 'f', 'i', '9031', 'r', '5519', '3955', 'd', '2093', 'c', 'y', '6591', '6463', 'h', '4371', '111', 'p', '3221', '4185', 'p', '8761', 'w', 'p']

Answer: c, d, f, g, h, i, p, r, w, y


Question: ['8301', 'd', 'p', 'l', 'm', '9099', 'o', '8045', 'e', 's', 't', '8853', 'v', '6375', 'q', '2505', 's', '4219', '3587', 'g', '651', '7129']

Answer: d, e, g, l, m, o, p, q, s, t, v


Question: ['4339', 'b', '8425', 'c', 'i', 't', '915', '4565', 'w', 'n', 'd', '957', '1959', '3983', '8107', '7839', '9347', 'o', '8439', '7389', 'r', 'r', '9075', 'y', '3991', '27', '6125', '1523', 'l', '5125', 'q', 'k', 't', 'z', '1537', '8095', 'c', 'j', '6281']

Answer:
b, c, d, i, j, k, l, n, o, q, r, t, w, y, z