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: ['s', 's', '6581', 'e', '7355', '1315']

Answer: e, s


Question: ['9271', '6393', '6005', 'x', '2301', '3999', 'p', 'z', 'j', '1033', '7555', 'r', 'r', 'y', '8917', '5939', '4031', 'e', '8095', 'g', '6095', 'a', '4133', '6471', '2129', '8021', '1093', 't', '8805', '545', 'k', '3249', 'l', '1561', '9909', 's', '1963', 'o']

Answer: a, e, g, j, k, l, o, p, r, s, t, x, y, z


Question: ['h', 'k', '7937', 'x', 't', '7515', '3539', '2319', '5607', '4025', '977', 'd', '7937', 'i', 'o', 'v', 'g', '5433', 'g', '727', 'q', 'l', '8651', '9059', 'h', '8819', '4139', '635', '1887', 'f', 'l', 'e', 'g', 't', 'a', 'a', 'n', 't']

Answer:
a, d, e, f, g, h, i, k, l, n, o, q, t, v, x