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]: ['1983', '1835', '6543', '6399', '4177', '9385', '7127', 'p', 'l', 'u', 'g', 't', '3423', 'g', 'b', 'l', '3133', '2429']
[A]: b, g, l, p, t, u


[Q]: ['w', 'g', '1649', 'a', '2115', '6763', 'r', 't', 'l', 's', 'y', '5659', 'a', 'b']
[A]: a, b, g, l, r, s, t, w, y


[Q]: ['9035', 'h', 'x', '6045', 'j', 'i', 'l', 't', '8693', 'a', 'w', '9799', 'h', 'x', 'g', '2719', '2531', '8091', 'c', '8801', 'h']
[A]:
a, c, g, h, i, j, l, t, w, x