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: ['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: ['x', 'b', '1467', 'y', '2101', 'y', 'm', '2745', 'z', '429', '7523', 'e', 'f']

Answer: b, e, f, m, x, y, z


Question: ['4499', '3093', 't', '5695', '5299', '5979', 'z', '6791', '8645', 'q', 'y', '6711', '55', '6073', 'v', 'f', 'a', '1235', 'x', '8007', 'k', 'r', '3065', 'n', '9273', '4963', 'a', '9865', 'i', 'd', '3333', '1457', '8077', '7017', 't', '3687', 'd', 'u', 'j']

Answer:
a, d, f, i, j, k, n, q, r, t, u, v, x, y, z