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: ['8311', 'w', 'f', '3431', '9863', '5817', '3969', '2705', 'x', 'm', 'k', 'z', 'z', '235', 'x', '417', 's', 'i', 'y', '8833', '8675', 's', 'm', '2149', '765', 'u', '1021', '7823', 'x', '7275', '3157', 'k']

Answer: f, i, k, m, s, u, w, x, y, z


Question: ['9113', '3625', 'u', '8189', '3649', '259', '5539', '1583', 'g', '4037', 'y', 'v', '8337', 'd', 'q', 'j', 'c', 'h', 'p', '1601', 'z', 'c', 'n', '1767', '1679', '1805', 'm', '4469', '2487', '6015', '973']

Answer: c, d, g, h, j, m, n, p, q, u, v, y, z


Question: ['6357', 'q', 'a', 'f', '7525', 'g', 'd', '4639', 'q', '7025', 'c', 's', 'q', 'v', 'l', '6961', 'k', '8125', '8849', '8127', 'l', '5943', 'v', 'h', '5621', 'r', '8983', 'd', '927', '5167', 'z', 'z']

Answer:
a, c, d, f, g, h, k, l, q, r, s, v, z