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: ['1945', 't', '4477', '4439', '6569', '2021', 'y', 't', '2725', '8947', '6921', '1373', '8107', 'g', 'c', 'w', 'x', 'b', '9117', 'k', '6567', '5073', '2307', 'e', 'b', '7405', 'e', 'x', '1419', 'd', 'o', 'n', 'a', '2647', 'z', '1459', 'n', '6137', 'u', 'b', 'q', '4459']
Example Output: a, b, c, d, e, g, k, n, o, q, t, u, w, x, y, z

Example Input: ['9351', 'v', 'h', 'z', 'g', 'f', 't', 'q', 'g', 'o', '4073', 'n', '6149', '1735', '157', 'm']
Example Output: f, g, h, m, n, o, q, t, v, z

Example Input: ['a', 'n', '6389', 'n', 'i', '7165', 'x', 'd', 'q', '7311', 'z', 'g', '9069', 'b', 'r', 'k', '3775', 'm', '5391', 'i', 'z', 'c']
Example Output:
a, b, c, d, g, i, k, m, n, q, r, x, z