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.

Ex Input:
['277', '8697', 'q', '2023', '5723', 'm', '8673', 'f', 'z', 'z', 'a', '9875', 'p', 'x', 'l', 'z', 'x', '619', '6509', 's', '2067', '571', 't']

Ex Output:
a, f, l, m, p, q, s, t, x, z


Ex Input:
['w', '1349', '3393', '7507', '2469', '8531', 'w', '6845', 'k', 'q', '2401', 'f', 'g', 'l', 'n', 'n', 'e', 'q', 'y', 'v', '3077', '4167', 'b', '5517', 'b']

Ex Output:
b, e, f, g, k, l, n, q, v, w, y


Ex Input:
['t', '4505', '8487', 'n', '7417', 'g', 'g', 'd', 'b', 'd', 'j', 'w', 'j', '2913', '9105', '5895', 'x', '1351', '307', '6061', 'k', 'w', '6227', '6935']

Ex Output:

b, d, g, j, k, n, t, w, x