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: ['5553', 'f', '3881', '8867', 's', 'd', 'a', '375', '7889', '3949', '2905', 'w', 'q', 'q', 'd', '4203', 'i', '2601', 'y', 'p', 'k']

Answer: a, d, f, i, k, p, q, s, w, y


Question: ['1593', '8165', 'q', '6689', 'b', 'r', '373', 'g', '6505', '415', '495', 'j', 'j', 'f']

Answer: b, f, g, j, q, r


Question: ['5035', '6503', '3099', '3187', '9061', '8801', '4801', '6677', 'g', 'n', 'c', 'v', '333', '6551', '903', 'e', '9957', 'd', '2315', 'p', '901', '7635', '7361', '6153', '6951', 'a', 'c', '8285', 'q', '1275', '379', 't', 'd', 'l', 'k', 'v', '8715']

Answer:
a, c, d, e, g, k, l, n, p, q, t, v