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.

['w', '1081', 'n', '2073', 't', '6351', '5591', 'a', '113', 'w', 'q']
a, n, q, t, w

['5433', '4011', '2113', '2299', 'e', '9829', 'd', 'q', 'e', '3921', 'a', 'q', '8953', 'q', 'g', 'w', 'z', 'u', '4425', 'b', 'q', '5315', 'b', 'u', 'h', 'y', '9733', 'b', 'c', '1225', 'a']
a, b, c, d, e, g, h, q, u, w, y, z

['4373', '2179', 'f', 'g', 'v', '6399', '1111', '3227', '6275', 'z', '9653', 'p', '3073', 'o', '153', 'l', 'j', '803', 'f', 'a', 'f', '3059', '9063', 'x', 'h', '6067', 'h', 'l', 'g', '1149', 'l', 'e', '5853', '1583', '8457', 'n', 'm', '5831', 'j', '8975', 's', 'm', 'j', '433']

a, e, f, g, h, j, l, m, n, o, p, s, v, x, z

