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: ['907', '2407', '1385', '3593', 'x', '4143', '2271', '8361', 'q', '5093', 'd', '257', 'm', 'a', '5751', '7845', '3925', '3517', '7753', 'e', '5803', '2629', 't', 'e', '845', '6157', '9787', '225', 'j', 'j', 'l', '1321', 'k', '2459', 'u', '9113', '3193', 'a', 'j', 't']

Answer: a, d, e, j, k, l, m, q, t, u, x


Question: ['s', 's', '3619', '6051', 'h', '213', '3937', 'v', 'p', 'y', '8449', '9337', '5327', 'a', 'a', 'w', '3985', 'n', 'm']

Answer: a, h, m, n, p, s, v, w, y


Question: ['p', '3981', 'e', '5949', 'p', '4075', '1919', 'w', 'r', '8059', '4303', 'f', '5201', '2255', '2737', '7395', '8809', 'j', 'z', 'n', '4797']

Answer:
e, f, j, n, p, r, w, z