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: ['1487', '8003', 'd', '7237', 'l', 'y', '2749', 'e', '9685', '2825', 'z', '7743', 'r', '9617', 'w', '4323', '2173', '8419', '2831', '8923', 'l', '2985', '303', 'y', '9409', 'i', 'h', 'e']

Answer: d, e, h, i, l, r, w, y, z


Question: ['5161', 'v', 'y', '6005', 'y', 'l', '5451', 'z', 'j', 'd', '4597', '9319', '1241', 'g', 'f', 'b', 'g', '683', '763', 'm']

Answer: b, d, f, g, j, l, m, v, y, z


Question: ['2451', 'y', '9743', 'b', 'j', 't', '9345', 'v', '4471', '7977', 't', '993', 'o', 'v', 'd', '641', 'f', 'i', '6069', 'p', '9539', 'k', '2701', '7865', '1767', 's', 'g', '5189', '6493', '149', '5321', 'g', 'l', '8991', '3925', '6595']

Answer:
b, d, f, g, i, j, k, l, o, p, s, t, v, y