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: ['w', '6291', '3939', '9569', 'u', '1635', '3359', '8335', 'n', '2799', '7359', 'k', 'm', '2817']

Output: k, m, n, u, w


Input: Consider Input: ['9483', '501', 'j', 'k', '3103']

Output: j, k


Input: Consider Input: ['125', 't', '2193', '39', 'j', 'i', '1217', 'u', 'j', '8183', 'w', 'h', '7613', 'u', 'c', '1691', 'b', 'l', 'h', 'c', '3241', 't', 's', '6337', 'w', '4121', '457', 'o', 'l', 'q', 'p', 'i', '1935', 'g', 'e', '3483', 'u']


Output: b, c, e, g, h, i, j, l, o, p, q, s, t, u, w