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.

Q: ['5431', 'o', 'u', 'l', 'f', 'd', 'r', '1479', '9357', 's', 'v', '6399', 'b', '7937', 't', '8497', 'r', '131', 'h', 'c', 'v', '8879', 'k', 'r', '4687', 'l', '1065', 'r', 'w', 'l', '3305', '461', 'q', 'h', 'b', 'e', 'e', 'w', '5999']

A: b, c, d, e, f, h, k, l, o, q, r, s, t, u, v, w
****
Q: ['5011', 'l', '925', 'e', 'b', '3077', 'm', '4541', '781']

A: b, e, l, m
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Q: ['1305', '3749', 'l', '3137']

A:
l
****