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: ['1233', '405', '8901', '7147', '8841', 's', 'v', '3131', 'p', 'd', 'y', '5873', '439']

Answer: d, p, s, v, y


Question: ['395', '8309', 'v', 'r', 'x', 'j', 'l', 'b', 'c', 'c', '3123', 't', 'a']

Answer: a, b, c, j, l, r, t, v, x


Question: ['8617', '4721', 't', '8757', 'w', '1267', 't', 'w', '4905', '4519', '6719', 'f', 'j', '9141', 'c', '9917', 'v', 'y', '8863', 'a', 'c', 'l', '3319', '9797', 'i', '9581', '9059', 'k', '8239', '5789', '1579', '1695', '5729', '6177', 'r', 't', '559', 's', '359']

Answer:
a, c, f, i, j, k, l, r, s, t, v, w, y