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: ['d', 'm', 'k', '3513', '8241', '5541', 'm', 's', '1993', '6163', '2753', 'd', 'b', 'm', 'i', '7647', '8631', '9119', '2165', 'x', '3911', '2769', '1673', '7195', 't', 'w', '5555', 'o', '3265']

Answer: b, d, i, k, m, o, s, t, w, x


Question: ['i', 'y', '8339', 'd', 'b', '7471', '6577', '9037', '4503', '6287', '1439', '8863', '9201', '2661', 'x', 'l', 'v', 'w', 'a', 'f', '8885', '519', '7631', 'g', '7203', '8605', '2429', '9165']

Answer: a, b, d, f, g, i, l, v, w, x, y


Question: ['s', '6779', 'w', 'k', 'v', 'j', 'u', 'z', 'l', 'y', '5873', 'i', 'j', 'g', 's', 'f', 'd', 'l', 'e', '3617', '3181', 'w', 'z', '6565', '8331', 'a', 'm', 'x', 'j', 'j', '8401']

Answer:
a, d, e, f, g, i, j, k, l, m, s, u, v, w, x, y, z