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.

[EX Q]: ['8381', 'j', '761', '5431', '7601', 'd', '4339', '1479', 'b', 'x', 'f', 'w', '2437', '7725', '6385', '411', 'w', 'w', 'i', '2769', '5709', '5703', 'k', '5301', '6503', '7833', 'y', '3813', '7061', '5531', 'n', '2251', 'y', '8941', '8481', 's', 't', 't', '3345', 'k', '1545']
[EX A]: b, d, f, i, j, k, n, s, t, w, x, y

[EX Q]: ['2527', '9123', '8717']
[EX A]: -1

[EX Q]: ['7875', 's', '1929', '3795', '2087', 'm', 'r', '9537', '4137', 'g', '695', '117', '1287', 'i', 't', '9167', 'o', '3073']
[EX A]:
g, i, m, o, r, s, t