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: ['3821', '385', 'y', '8457', '6623', 'g', '5923', 'a', '7193', 'v', 'm', '8915', 'v', '5873', 'p', 't', 'w', 'y', '3617', 'h', 'w', 'j', '8047', 'u', '2271', 'v', 'a', '2181', 's', '1051', 'b', 'a', '9967', '987', 'z', '2255', '6349', '1249', '1397', 'q']

Answer: a, b, g, h, j, m, p, q, s, t, u, v, w, y, z


Question: ['8739', 'v', 'm', '6277', 'l', 's', '109', '8057', '3835', 'd', 'u', 'f', 'w', 'd', 'p', '7705', '3643', '4455', 'u', 'p', 'u', '9407', 'g', 'w', '595', 'z', '6827', '6879', 'w', 'w', '6973', 'm', 'e', '1553', 'v', '3529', '8953', '3903', '5713', '8249', 'e', '1113', 'b', 't', 'r']

Answer: b, d, e, f, g, l, m, p, r, s, t, u, v, w, z


Question: ['1493', 'z', '2945', '4545', 'k', 'c', '7897', '1259', '3997', 'c', 'r', 'p', '1689', '3675', 'v', 'v', '5523', '6513', '2745', 'e', 'p', '4211', '7545', 'k']

Answer:
c, e, k, p, r, v, z