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:
['k', 'j', 'v', '5277', '8607', 'n', '1109', 'e', 'k', '6579', 'o', '2909', 'u', 't', '9685', '8443', '9257', '8071', 'y', 'b', 'h', '4767', 'a', 'j', '8455', 'b', '7733', '2553', 'e']

Ex Output:
a, b, e, h, j, k, n, o, t, u, v, y


Ex Input:
['p', 'g', 'q', 'e', '8045', '9999', '9555', '7995', '7195', 'z', 't', '5223', '3699', 'i', '4797', '3817', 'x', 'y', 'w', 'o', '8915', '7803', 'n', '1117', 'c', '9647', 'p', 'e', '9669', '4845', '9255', '4545', '3693', '6871', 'w', '4327', '3285', 'k', 'f', 'x', 'i', 'b', '5967', '6601']

Ex Output:
b, c, e, f, g, i, k, n, o, p, q, t, w, x, y, z


Ex Input:
['4775', '9913', 'b', '5929', '1479', '3471', 's', 'i', '7269', '9403', 'a', '8309', '1291', '2319', 'n', '3915', 'y', '5325']

Ex Output:

a, b, i, n, s, y