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: ['305', '95', 'e', 'q', 'e', '341', 'u', 'w', '5911', '6851', 's', 'u', '2355', 'd', '4151', 'w', '4421', '1129', '8065', 'k', 'q', '3649']

Answer: d, e, k, q, s, u, w


Question: ['8631', '4059', '1563', '2325', '307', '6041', 'z', 'k', '5605', 'j', 't', 'w', 'j', '2651', 'd', 'w', 'd', '6599', '3331', 'z', 'l', '9459', '3795', 'v', '5209', '1985', '5747']

Answer:
d, j, k, l, t, v, w, z