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: ['2313', '2073', 'd', 'e', 'o', '793', '4999', 'f', 'c', '4473', '4519', 'u', 'n', 'k', '69', '475', 'a', 'j', 'q', 'x', '5869', '9523', 'z', 'v', '9265', '5989', 'p', 'm', 'g', 'y', 'b']

Answer: a, b, c, d, e, f, g, j, k, m, n, o, p, q, u, v, x, y, z


Question: ['c', '1693', 'l', 'u', 'x', '3609', 'h', '4159']

Answer: c, h, l, u, x


Question: ['3205', 'v', 'k', 'z', '6103', '4879', 's', '7967', '9815', 'o', 'u', '6213', '3603', 'b', 'e', 'f', '3065', '9775']

Answer:
b, e, f, k, o, s, u, v, z