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: ['9925', 'f', '6149', 's', 'd', 's', '75', '8577', '2319', 'b', '3769', '5211', 'q', 'm', '8127', 'f', '3801']

Answer: b, d, f, m, q, s


Question: ['q', 'c', 'o', 'e', 'n', 'q', 'w', '9475', 'w', '863', 'r', '2219', '3483', '5035', '8209', '7957', 'b', '3735', '1423', 'l', '3409', '7639', 'd']

Answer: b, c, d, e, l, n, o, q, r, w


Question: ['1561', 'k', '9513', '3495', 'w', 'z', 'f', 'j', '4569', 'p', 'u', '8121', '6281', '6521', 'd', '6201', 'a']

Answer:
a, d, f, j, k, p, u, w, z