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: ['w', '1081', 'n', '2073', 't', '6351', '5591', 'a', '113', 'w', 'q']

Answer: a, n, q, t, w


Question: ['o', 'v', 'w', '7939', '571', '395', '3707', 'm', 'd', 'u', 'o', 'r', '4211', '9645', '8731', '2441', 'y', '8147', '8809', 'e', 'b', '6835', 'i', '2083', 't', '3481', 'f', 'f', '5559', '3601', 'e', '5637', '5185', 't', '6777', '3419', '8637', 'p', 's', 'o', 'x']

Answer: b, d, e, f, i, m, o, p, r, s, t, u, v, w, x, y


Question: ['c', 'x', '8267', '453', '5149', '2845', 'n']

Answer:
c, n, x