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: ['t', 'm', '7071', 'j', '353', 'n', 'a', 'm', '9211', 'i', '9537', 'q', '7669', '869', '8753', '8071', '375', '9971', 'c', 'n', '5851', 'u', '2491', '2697', '2789', '4683', '879', 'q', 'g', 'p', 'd', 'x', 'r', 'i', '8171', '5449', '2477', '1151', 'z', '3845', '1079', 'j', 'n', 'p', '8199']

Answer: a, c, d, g, i, j, m, n, p, q, r, t, u, x, z


Question: ['a', 'y', 'v', 'f', 'x', 'k', 'f', 'j', '6245', '6289', 'd', '6909', '8701', 'm', '3277', 'f', 'j', 'j', '9227', '8663', '5771', 'j', 'n', 'u', '7837', 's', '2539', '6363', 'g', 'a', '1009', 'v', '1483', 'x', 'i']

Answer: a, d, f, g, i, j, k, m, n, s, u, v, x, y


Question: ['h', 's', 'v', '5709', '1353', '8717', '4701', 'f', '2003', 's']

Answer:
f, h, s, v