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: ['4993', 'n', '7115', 'f', 'd', 'q', '249', '3203', 'w', '5689', '4103', '7129', '603', 'e', 'z', '5571', '3241', '6029', '2721', '8451', 'o', '7841', 'p', '6271', 'r', 'b', '9481', '4045', 'v']

Answer: b, d, e, f, n, o, p, q, r, v, w, z


Question: ['57', 'j', 'n', '877', 'u', 'w', 'j', 'f', '8977', 'h', '469', '9417']

Answer: f, h, j, n, u, w


Question: ['l', '7795', '9653', '443', '9093', 't', 'a', 'z', 'z', '2107', '6841', 'o', 'x', '751', 'm', '4307', '8059', '8089', 'e', 'w', '1735', 'i', '8259', 'l', 'b', 'd', '6895', 'x', 'c', 'a', '9325', '6545', 'a', '6057', 'g', 'n', 'x', 'c', '3049', '5191', 'z', '6283', 'd']

Answer:
a, b, c, d, e, g, i, l, m, n, o, t, w, x, z