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: ['4041', 'l', 'g', '9571', '9295', '1395', 'l', 'p', 'f', 'w', 'g', '1721', '2421', 'w', 'z', '2235', 'p', '7851']

Answer: f, g, l, p, w, z


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

Answer: u, x


Question: ['o', 'a', 'b', '7015', '8085', '9159', 'a', 's', 'u', 'j', '7941', 't', '1551', 'b', '1161', 'p', '7475', 'c', 'k', '7639', 'u', '1951', '8271', '8735', 'l', 'f', 'y', 'c', '6997', 'z', '6715', 'a', '6341', 'x', '7337', '8927', 'i', '3511', 'o', '1859', 'u', '1255', 'w', '9921', 's']

Answer:
a, b, c, f, i, j, k, l, o, p, s, t, u, w, x, y, z