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: ['w', '1349', '3393', '7507', '2469', '8531', 'w', '6845', 'k', 'q', '2401', 'f', 'g', 'l', 'n', 'n', 'e', 'q', 'y', 'v', '3077', '4167', 'b', '5517', 'b']

Answer: b, e, f, g, k, l, n, q, v, w, y


Question: ['i', '9575', '8995', 'm', 'o', '3015', '4005', '6909', '7195', '3361', 'j', '5253', '9523', '8879', '5861', 'e', 'y', 'e', '1525', 'i', '807', '8469', '3333', '4017', '2237', '3387', 'o', '643', 'p', '7129', '6243', 'y', '4913', 'z', 'f', '6909', 'f', '4347', '7227', 'o', 's', '9909', '8611']

Answer: e, f, i, j, m, o, p, s, y, z


Question: ['j', 'v', '4471', '6919', 'r', '6791', 'f', 'u', 'r', 'c', 'g', 'i', '2919', 'p', 'n', 'f', '4543', 'v', '8717', '2221', 'r', 'o', 'j', 'o', 'h', 'i', '8355']

Answer:
c, f, g, h, i, j, n, o, p, r, u, v