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: ['8829', 'm', '5369', 'q', '5737', '7799', '5705', 'p', 'w', '1983', '4849', 'h', '6771', 'p', 'y', '1071', 'u', '6401', '7723', 'p']

Output: h, m, p, q, u, w, y


Input: Consider Input: ['v', 'l', 'v', '7673', '8975', 'u', '2471', '4151', '3615', '1139', 'i', 'z', '8833', 'v', '341', 'l', 'n', 'l', 'd', '9207', '1861', '3901', 'a']

Output: a, d, i, l, n, u, v, z


Input: Consider Input: ['2641', '6253', 'k', 'e', 'u', 'p', '2149', '5295', 'b', '4903', '4045', '1951', 't', '6761', '4909', 'z', 'g', 'r', 'l', 'm', '5145', '5163', '865', 'v', '1905', 'c', '789', 'b', '5831', '8433', 'k', '8895', '5181', 'b', '4619', 'q', 'h', '9435', '45', 'i', 'i', 'v', '8199']


Output: b, c, e, g, h, i, k, l, m, p, q, r, t, u, v, z