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: ['r', 'j', '437', 'b', '5223', 'n', 'v', '437', 'd', '8285', 'k', 'j', 'r', 'p', 'n', 'e', 'n', 'j', 'o', '2651', 'j', '6365', 'q', 'q', '2159', 'g', '3641', '7727', 'c', '1197', 's', 't', 'n']

Answer: b, c, d, e, g, j, k, n, o, p, q, r, s, t, v


Question: ['3561', 'd', '9697', 'd', '7761', 'a', '2833', 'c', '2921', 't', '691', 'g', '4797', 'b', '3913', 'f', 'q', '7807', 'j', '3577', 'j', '1775', '2897', '2589', '993', '8595']

Answer: a, b, c, d, f, g, j, q, t


Question: ['6129', 'q', 'z', 'u', '2077', 'l', 'd', 'd', '2325', '2813', '8807', 'm', 'm', 'z', 'e', 'r', '8917', '4885', '3541', 'q', '8585', 'v', 'g', '5791', '7505', '9601', 't', '3869', 'g', '9315', '9435', 'o', '9035', 'p', '7885', 'a', 'e', '5273', '3643', 'n', 'o', '8947', 'l', 'o', '6853']

Answer:
a, d, e, g, l, m, n, o, p, q, r, t, u, v, z