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: ['o', 'd', '6495', '5211', '341', 'v', '385', 'v', 'g', 'v', 'l', '7631', '2675', 't']

Answer: d, g, l, o, t, v


Question: ['k', '6595', '1595', 'v', 'h', 'b', '8815', '6681', 'j', '7581', 'p', '9095', '5453', 'r', 'y', '7755', 'x', '1853', 'k', 'q', 'u', 'j', 'q', '9651', 'o']

Answer: b, h, j, k, o, p, q, r, u, v, x, y


Question: ['h', '7009', 'k', 'x', '7649', 'i', '9925', '9593', 'f', 'x', 'd', 'n', 't', '1433', 'e', 'r', 'w', '6753', 'r']

Answer:
d, e, f, h, i, k, n, r, t, w, x