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.

Example Input: ['t', 'r', '2959', '2517', 'a', '9959', '729', '511', 'y', 'r', '465', 'c', '687', 'm', 'b', 'm', '3449', '9713', 'g', '8275', '8823', 'a', 'z', 'w', '2185', '6283', '8457', '8137', '7163', '8329']
Example Output: a, b, c, g, m, r, t, w, y, z

Example Input: ['4371', '9499', 'e', 'w', '9969', '8367', '2897', '1745', 'i', '7049', '9773', 'h', '9649', 'u', '4673', '8513', '8547', 'z', '1995', '7739', '2215', '171', 'c', '7527', '2479', 't', '5223', 'p', '2313', '3243', '2281', 'r', 'c']
Example Output: c, e, h, i, p, r, t, u, w, z

Example Input: ['729', '8673', 'g', '7667', '6029', 'v', '2735', '1915', 'o', 'c', '5107', '4415', 'z', '1373', 'l', 'j', 'y', 'r', 'o', 'r']
Example Output:
c, g, j, l, o, r, v, y, z