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.

Input: Consider Input: ['8879', 'x', '1383', '4925', '2867', 'j', 't', 'e', 'w', 'p', 't', 'w', 'l', '7447', '1877', '7747', 'k', 'b', 'x', '8565', 'q', '8575', '5711', '2949', '5637', '2197', '4905']

Output: b, e, j, k, l, p, q, t, w, x


Input: Consider Input: ['6955', '721', '2763', '8121', '9109', '6341', 'p', 't', 'x', '6963', '1137', 'z', 'u', '1949', '7029', 't', '9539', 'a', 'u', '1873']

Output: a, p, t, u, x, z


Input: Consider Input: ['s', '1293', 'd', '2049', '7257', 'h', 'v', '7193', '9465', '1747', '6793', 'd', 'j', 'j', '9739', 'i', 'o', 'a', '6755', '2541', '3103', '4481', '4713', '4079']


Output: a, d, h, i, j, o, s, v