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: ['8315', 'b', '4333', 'f', '6507', '6211', '3475', 'c', 'e', '8039', '661']

Answer: b, c, e, f


Question: ['d', '5285', 'z', 't', 'i', '719', 'z', 'b', '3603', '4781', 'o', 'g', 'j', 'd', 'r', 'a', 'x', '5829', '4907', '7395', '993', '2109', '1745', '415', '7525', '1029', '7791', '5321', 'h', '6391', 'g', '4613', '9191', 'o', '7365', '1811', '9695', 'w']

Answer: a, b, d, g, h, i, j, o, r, t, w, x, z


Question: ['f', 'l', 'z', 'k', '425', 'p', 'h', '1949', '2239', '7065', 's', 'm', '3525', 'f', '7133', '5719', 't', 'l', 'q', 'n', '8089', 'u', '3909', '3137', 'b', '9693', '5619', 'j', '8835', '587', 'e', '221', '3281', '8349', 'x', 'x', '7355']

Answer:
b, e, f, h, j, k, l, m, n, p, q, s, t, u, x, z