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: ['5463', '5683', 'w', '4071', '3997', 'i', '9677', 'q', 'l', 'v', 'w', '5325', '197', 'g', 'g', '3227', '3477']

Answer: g, i, l, q, v, w


Question: ['6175', '9441', '7127', '5979', 's', '1367', 'e', 'm', '7083', '1787', '8375', '2851', '3475', 'r', '697', 'g', 'z', 'm', '4207', 'c', '7971', 'z', '9339', 'd', 's', '3507', '9003', 'i', 'y', 'w', 'j', 'i']

Answer: c, d, e, g, i, j, m, r, s, w, y, z


Question: ['5613', '9391', '9189', 'j', '1633', '1581', 'l', '9267', '7921', '8725', 'u', '4755', '2529', '6639', '8611', '6991', '4173', '877', 'l', '1115', 'e', 'v', 'z']

Answer:
e, j, l, u, v, z