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: ['2505', '4199', 'e', '5433', '8795', 'q', 'i', '9357', 'o', '257', '8235', 'b', '1339', 'w', '1463', 'm', '277', '3211', '3863', 'r', 'm', 'i', '5793', '7451', '4787', '4739', 'k', 't', 'o', '7453', '9385', 'v', 'l', 'y', 'f', 'r', 'p', 'w']

Answer: b, e, f, i, k, l, m, o, p, q, r, t, v, w, y


Question: ['b', 'd', '8153', 'u', '3695', '5317']

Answer: b, d, u


Question: ['6131', 'k', 'a', 'f', 'l', '4027', '4485', 'j', '279', '4727', 'p', '1089', 'l', '3411', '1307', '3883', 'u', 'w', '8851', 'f', 'a', 'i', '6461', 'w', 't', '7165', '9089', 'k', 'v', '3683']

Answer:
a, f, i, j, k, l, p, t, u, v, w