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: ['7823', '2933', 'k', '4139', '5585', 'f', 'c', 'm', '2035', 'q', 'z', 'l', '1999', 'q', 'p', '7291', '2091', 'v', '423', 'e', 's', '6089', '4763', '6739']

Answer: c, e, f, k, l, m, p, q, s, v, z


Question: ['c', '6027', 'o', 'h', 'l', '7893', 'u', 'f', '7661', '4715', '1373', '4799', 'd', 'z', '411', '4753', 'd', '8241', '1589', '4173', '3921', 'j', 'o', '5067', '8879', 'e', 'm', '9543', '9625', '855', 'u', 'd', '5859', '4243', '5747', '5147', '7315', 'd', 'x', 'q', '7841', '7397', 'm']

Answer: c, d, e, f, h, j, l, m, o, q, u, x, z


Question: ['u', '2047', 't', 'k', '9323', 'k', 'w', '889', 'w', 'o', 'b', '4121', 'p', '9079', 'j', '6127', '9393', '7755', '3877', 'v']

Answer:
b, j, k, o, p, t, u, v, w