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]: ['m', '7807', 'n', 'w', '5097', '1023', '2723', 'u', '3055', '7285', 'f', 'm', 'w', '5197', '9743', '7519', '4451', 'c', 't', '1939', '5847']
[A]: c, f, m, n, t, u, w


[Q]: ['2453', 'r', 'd', '8499', 't', 's', 'h', 'a', 'm', '9271', 'g', '2599', '6209', 'o', 'i', '4069', 't', '6793', '7679', '6643', '7359', 'm', 'f', 'w', '775', '3347', '6161', '9745', 'i']
[A]: a, d, f, g, h, i, m, o, r, s, t, w


[Q]: ['4761', '1651', '2569', 'z', '3027', '8613', '2249', 'm', '175', '4165', 'h', '8597', 's', '3625', 'g', 'j', '3327']
[A]:
g, h, j, m, s, z