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: ['8451', 'x', '9965', '9303', 'm', 'f', '4205', 'y', 'n', '8521', '9995', 'z', 's', '3519', 'k', 'e', 'o', 'k', '9611', 'q', 'l', 'p', '3339', '4023', 'n', 'd', '8903', 'a', 'k', 'u', '4009', 'e', 'm', '989', '4495']

Answer: a, d, e, f, k, l, m, n, o, p, q, s, u, x, y, z


Question: ['9833', '3383', 'h', '3545', '2899', 'y', 'p', 'q', '1901', '3317', '5641', 'v', 'c', 'u', '5521', 'e', '7997', '2439', '5573', '4119', 'k', '8291', '1009', '8253', '405', '233', 'p']

Answer: c, e, h, k, p, q, u, v, y


Question: ['3405', '2361', 'u', 'b', 'a', 'z', 'e', '1253', '1663', 'u', '5533', 'h', 'z', 'o', '6455', '6995', 'w', '5127', '5493', 's', 'o', 'v', '6127', '6565', 'o', 'd', '3437', 'p', 'a', '387', 'r', '9621']

Answer:
a, b, d, e, h, o, p, r, s, u, v, w, z