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: ['1063', 'f', 'm', 'i', 'x', 'i', 'd']

Answer: d, f, i, m, x


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: ['969', 'q', 'm', '4933']

Answer:
m, q