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: ['6143', 'y', '5505', '9813', 'r', 'v', 'u', '8681', '2387', 'u', 'o', 'm', '9793', 'm']

Output: m, o, r, u, v, y


Input: Consider Input: ['i', 's']

Output: i, s


Input: Consider Input: ['g', '1107', '6215', 'o', '6277', '8197', 'q', '3859', '2659', 'h', '6837', '5607', 'm', '915', 'g', 'j', 'w', '789', 'm', 't', 'j', '9541', '7397', '1979', '1663', 'y', '9165', '9867', '5979', '8185', 'y', '489', '4557', '3531', '6611', 'y']


Output: g, h, j, m, o, q, t, w, y