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: ['i', 'h', '8299', 'e', 'c', '5543', '5241', 'f', '3985', 'f', 'z', '1245', 'e', 't', 'g', '5199', '9217', 'q', 'j', 'p', '767', 'z', '1803', 'k', '7303', '3187', '2507', '6471', '3337', '6037', '9291', 'a', 'l']

Answer: a, c, e, f, g, h, i, j, k, l, p, q, t, z


Question: ['2705', 'n', 'r', '8259', '6839', '3239', 'w', 'z', '2611', '2957', '2303', '6315', '7801', 'c', 'w', 'm', '5049', '6465', '599', 'h', 'q', '7559', 'n', '9917', 'v', 'l', '643', '6415', '3587', 'c', '917', '4435', 'p', 'a', '317']

Answer: a, c, h, l, m, n, p, q, r, v, w, z


Question: ['l', '3611', '7085', 'w', '597', '5885', 'r', 'v', 'p', '7987', 'd', '1027', 'i', '7793', '2395', '8423', 'e', '4491', 'z', 'z', 'w', '7167', 'y', '5951', 'r', '1741', '5175', '4621', '9307', '7377']

Answer:
d, e, i, l, p, r, v, w, y, z