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: ['3307', 'r', '2665', '3453', 'f', 'd', 'v', '3801', '3153', '3137', 'y', 'i', '9681', 'k', '9253', 'y', 'i', '8631', '2375', '5131', 'r', 'z', '8645', '595', 's', '6749', '2665', '709', '8203']

Answer: d, f, i, k, r, s, v, y, z


Question: ['6209', 'x', 'j', 'w', '7965', '4905', '6297', '4291', '7183', 'a', 'l', '5267', 'r', '5935', 'a', '7865', 'h', 'p', '6117', 'a', 'y', 'y', 't', 'v', '7271', 'e', 'e', 'z', 'i', 'l', '4731', '2059', 'm', '5703', 'k', 'f', '8125', 'e', '7569', 'r', '2287', '593']

Answer: a, e, f, h, i, j, k, l, m, p, r, t, v, w, x, y, z


Question: ['b', 'd', 'p', '669', 'x', 'f', '6809', 't', '8609', 'i', '4865', '5077', '7939', 's', 'j', 'r', 'g', '357', '3263', '7733', 'j', '1597', 'c', 't', '8895', 'i', '7201', 'g', '7333', 'q', 'b', '777', '6599', '1501', 'c', 'b', 'u', '4611', 'b', 'j', '531', '1559', '3181', '1407']

Answer:
b, c, d, f, g, i, j, p, q, r, s, t, u, x