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: ['9579', 'm', 'v', 'r']

Output: m, r, v


Input: Consider Input: ['6175', '9441', '7127', '5979', 's', '1367', 'e', 'm', '7083', '1787', '8375', '2851', '3475', 'r', '697', 'g', 'z', 'm', '4207', 'c', '7971', 'z', '9339', 'd', 's', '3507', '9003', 'i', 'y', 'w', 'j', 'i']

Output: c, d, e, g, i, j, m, r, s, w, y, z


Input: Consider Input: ['b', 'n', 'k', '5865', '9841', 'u', '9807', 'n', 'h', '5977', 'n', 'm', 'd', '2147', 'j', 'e', '4719', 'c', 's', '9219', 'i']


Output: b, c, d, e, h, i, j, k, m, n, s, u