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: ['6627', '8037', 'q', 'e', 'j', 'p', '9613', '9317', 'm', 'm', '5345', 'f', '8105', '5665', '4175', '4793', '3707', 'i', 'b', '6745', '747', '8329', '1481', 'b', '8949', 'n', '4803', '1359', '3533', 'f', '543', '3003', '6943']

Answer: b, e, f, i, j, m, n, p, q


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

Answer: t, x


Question: ['201', 'z', '1551', '7341', 'p', '1661', '8081', '3045', '7241', '6509', 'q', 's', '6073', '2019', 'm', 'y', '471', '1149', '9397', 'a', '4461', '4235', '1391', 'r', '3767', 'a', 'a', 'm', '5319']

Answer:
a, m, p, q, r, s, y, z