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: ['575', 'u', 'c', '8113', '2853', '3661', '9427', '3071', '4069', '835', 'w', 't', 'w', 't', 'v', 'g', 'c', '5497', '1703', '8433', 'g', '3545', '2887', 'z', 'a', '2241', '5799', '5915', 'u', '4015', '8327', 'z', 'a', 'w', '8311', '289', '8575', 't', 'b', '2873', 'r', 'z', 'x', '1165', '9881']

Answer: a, b, c, g, r, t, u, v, w, x, z


Question: ['n', 't', '2901', '9697', 'a', 'j', 'x', 'a', '4437', '2255', '2177', 's', '3173', 'j', 't', '5713', '4091', '4253', '5553', 'i', '4533', 'i', 'e', '6899', 's', '3541', '2139', '2705', 'm', 'u']

Answer: a, e, i, j, m, n, s, t, u, x


Question: ['623', '5275', '9955', '6329', '7069', '4487', '659', '2343', 's', '4521', 'w', '1251', 'l', '4921', '4951', '8319', 'l', 'l', '381', 'y', 's', '1875', '9731', '5129', '9927', '8743', '3659', '6405', 'p', '8123', '4371', '869']

Answer:
l, p, s, w, y