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:
['r', 'q', '3649', 't', '3941', 'z', '3729', 's', 'g', '6905', 'h', 'v', '1085', '6353', 'a', '9395', '5433', 'a', '2565', 'p', 'a', 'h', '1491', 'j', 'b', 'v', 'e']

Ex Output:
a, b, e, g, h, j, p, q, r, s, t, v, z


Ex Input:
['t', 'h', '6141', 'g', 'f', 'z', 'n', 'b', 'k', '9059', 'y', 'p', '4289', '2683', 'a', '3267', 'w', 'p', 't', '3623', '7759', 'a', 'o', 'm', '9815', 'q', 'u', '8051', '6871']

Ex Output:
a, b, f, g, h, k, m, n, o, p, q, t, u, w, y, z


Ex Input:
['o', 'f', 'a', 'o', '2603', 'c', 'z', 'z', '2153', 'w', '5323', '2995', '5631', '6455', 'w', 'w', '2565', 'k', '9787', '6567', '1027', '6167', '1059', 'd', '6559', 'k', 'b', 'n', '4609', '2711', '2981', 'j', '4315', '1553', '9261', 'e', '8437', '4621', 't', '8143', '8187', 'a', 'm', '307']

Ex Output:

a, b, c, d, e, f, j, k, m, n, o, t, w, z