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', '5341', 'b', '6243', 'v', '877', '1087', '6763', '5241', '3369', '9119', 't', 'v', 'j', '8261', 'o', 'b']

Answer: b, j, o, t, v, w


Question: ['s', 'w', '8949', '4025']

Answer: s, w


Question: ['r', 'h', 'n', '7289', '9623', 'q', '6129', 'j', 'z', 'v', '3115', '8853', '2303', 'f', 's', '9727']

Answer:
f, h, j, n, q, r, s, v, z