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: ['q', 'c', 'o', 'e', 'n', 'q', 'w', '9475', 'w', '863', 'r', '2219', '3483', '5035', '8209', '7957', 'b', '3735', '1423', 'l', '3409', '7639', 'd']

Answer: b, c, d, e, l, n, o, q, r, w


Question: ['o', '369', 'z', '5721', 'w', 'v', '4973', '7773', 'k', '3071', '5103', '425', '4239', '7977', 'n', 'i', 'k', '8117', '9843', 'n', 'd', '1353', 'h', 'd', 'v', 'z', 'j', '8727', '6997', 'x', '767', '4331', 't']

Answer: d, h, i, j, k, n, o, t, v, w, x, z


Question: ['1671', '2349', '9795', 'x', '699', 'y', '709', 'q', '2089', '6105', 'j', 'w', '1761', '9045', 'f', 'w', 'h', '2765', 'n', '8609', '7765', 's', '2825', 'i', '4239', 'v', 'r', 'l', '9863', '8249', 'j', '7833', '8645', '7139', 'u', '8989', '1311', '7149', 'g', 'd']

Answer:
d, f, g, h, i, j, l, n, q, r, s, u, v, w, x, y