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: ['653', '1969', '6235', '6283', 'd', 'e', '465', 'e']

Answer: d, e


Question: ['8235', 't', '1695', '9899', '3633', 't', '1823', 'r', 'x']

Answer: r, t, x


Question: ['9115', '1239', '5699', 'x', 'a', '7115', '8713', 'i']

Answer:
a, i, x