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: ['4397', '2685', '9539', '4343', '6697', '7693', 'g', 'c', '3587', '4691', 'j', '8931', '7397', '2103', '3431', 'u', 'l', 's', 'v', 'q', 'd', '1289', 'h', '1695', 'h', 'j', 'e', '1225', 'e', '7893', 'o', 'i', '3351']

Answer: c, d, e, g, h, i, j, l, o, q, s, u, v


Question: ['t', 'x', '1699', '8727']

Answer: t, x


Question: ['y', 'i', '257', '3695', 's', '6717', '4817', '4117']

Answer:
i, s, y