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: ['7417', '2597', '2633', '7721', 'v', 'l', 'p', '4389', 'l', '3965', '6279', 'm', 'v', 'o', 'd', 'o', 'h', 'd', 'r', 'e', '8993', '2711', 'o', 'q', '1399', 'i']

Answer: d, e, h, i, l, m, o, p, q, r, v


Question: ['9025', '3259', '4863', 'u', '6443', '9931', '627', 'x']

Answer: u, x


Question: ['k', 'b', 'i', 'v', 'l', 'z', '4549', '4337', 'a', 'z', '5029', '7563', 'r', 'q', '7293', 'v', 'u', 'p', '2369', 't', 'u', 's', '8897', '6593', 'm', 'k', '1469']

Answer:
a, b, i, k, l, m, p, q, r, s, t, u, v, z