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: ['x', 'b', '1467', 'y', '2101', 'y', 'm', '2745', 'z', '429', '7523', 'e', 'f']

Answer: b, e, f, m, x, y, z


Question: ['b', 'd', '8153', 'u', '3695', '5317']

Answer: b, d, u


Question: ['6117', '381', '1307', '883', 'e', '5041', '9103', '7421', 'x', 'w', 'g', 's', 'e', 'g', 'n', 'w', 'g', 'm', '5587', 'y', '2493', '9773', '807', 'u', 'd', 'a', '4569', 'i', 'z', 'a', 'h', 'c', '8651', '4517', 'm', '8695', '3379']

Answer:
a, c, d, e, g, h, i, m, n, s, u, w, x, y, z