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: ['z', '3219', '6399', '2357', '7597', '357', 'k', 'k', 'u', 'd', '6115', 'w', '2921', '8809']

Answer: d, k, u, w, z


Question: ['3191', '2655', '239', '2585', '3369', '7815', '5919', '8269', '5633', 'x', '8085', '2909', 'y', '2465', 'i', '1579', 'u', '2371', 'l', '1949', '51', 'e']

Answer: e, i, l, u, x, y


Question: ['8809', '5641', 'q', 'q', '3501', 'u', '1803', 'v', 'f', '4321', '7541', 'l', '8705', 'e', '8049', 'm', 'v', '8617', '3365', 'b', '977', 'c', 'q', 'k', '1505', 'd', '3273', 'k', '3649', '6405', 'x', 'r', 'w', '2613', '3715', 't', '2711', '5505', 'v', '7615', '5479', '6637']

Answer:
b, c, d, e, f, k, l, m, q, r, t, u, v, w, x