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: ['4993', 'n', '7115', 'f', 'd', 'q', '249', '3203', 'w', '5689', '4103', '7129', '603', 'e', 'z', '5571', '3241', '6029', '2721', '8451', 'o', '7841', 'p', '6271', 'r', 'b', '9481', '4045', 'v']

Answer: b, d, e, f, n, o, p, q, r, v, w, z


Question: ['9273', '5219', 'e', '9413', 'v', 'h', '5657', '797', '2303', '2119', '4791', '2757', '4983', 'h', '9681', '4503', '6657', 't', 'i', 'g', '9375', '9901', 'm', 'y', '6461', 'h', '6663', '9493', '5897', '8829', 'd', 'x', '901', '833', 'u']

Answer: d, e, g, h, i, m, t, u, v, x, y


Question: ['7483', 'g', '9967', 'm', 'm', 'v', '8385', 'b', 'l', 'x', 'w', 'a', '4063', '7599', 'u', 'i', '7401', 'i']

Answer:
a, b, g, i, l, m, u, v, w, x