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: ['2453', 'r', 'd', '8499', 't', 's', 'h', 'a', 'm', '9271', 'g', '2599', '6209', 'o', 'i', '4069', 't', '6793', '7679', '6643', '7359', 'm', 'f', 'w', '775', '3347', '6161', '9745', 'i']

Answer: a, d, f, g, h, i, m, o, r, s, t, w


Question: ['p', 'k', 'i', '753', 'u', 'm', '3817', '1597', 'l', 'm', 'a', 'i', 'b', 's', 'c', '2561', 'x', '5363', '1173', '8657', '2033', 'b', 'p', '3093', 'k', '6535', '307', '9925', 'b', 'q', 'q']

Answer: a, b, c, i, k, l, m, p, q, s, u, x


Question: ['j', 'd', '3797', '1385', '4101', '1733', 'd', 'q', 'f', 'n', '253', '741', '929', 'b', '6829', 'n', 'c', 'q', '6335', 'd', 'l', 'j', 'l', '7017', 'o', '239']

Answer:
b, c, d, f, j, l, n, o, q