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]: ['3019', 'g', 'q', 'u', '611', 'z', '3671', '8119', '1679', 'h', '2631', '655', 'k', '2837', 'e', 'f', 'e', 'f']
[A]: e, f, g, h, k, q, u, z


[Q]: ['c', '4881', '6893', '3729', 'j', '2385', 'q', 'v']
[A]: c, j, q, v


[Q]: ['9285', '3357', '1589', '7545', '503', '4011', 'n', '4183', '7799', 'z', '5065', '945', 'j', 'n', 'm', '4719', '9267', 'z', 'u', '1161', '9727', 'o', 'm', '8035', 'g', 'i', '7039', '1067', 'a', '4753', '1203', 'q', 'r', 'g', '731', '5269']
[A]:
a, g, i, j, m, n, o, q, r, u, z