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: ['j', 'r', 'z', 'f', '1485', '2419', 't', 'd', '6023']

Answer: d, f, j, r, t, z


Question: ['5761', '2289', '577', 't', '125', 'i', 'g', '9693', '747', 'd', '4829', '9587', 'f', 'k', 'w', 'v', '8607']

Answer: d, f, g, i, k, t, v, w


Question: ['r', '9489', 'e', 'n', '6323', 'd', '3163', '265', '8587', '7891']

Answer:
d, e, n, r