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:
['p', '4329', '2437', '6279', 'u', '459', 'f', 'c', 'i', 'w', 'n', 't', '429', 'n', '73', '4995', 'p', 'z', '8459', '6133', 'y', 'r', '4057', 'a', '2717', '7803', 'r', 'm', '2879', '6989', '7223', 'v', '7929']

Ex Output:
a, c, f, i, m, n, p, r, t, u, v, w, y, z


Ex Input:
['n', 'h', 'j', '5945', '8511', 'y', '7739', '4717', '2483', 'p', '9545', '7647', '9863', '5591', '5393', 'i', '9225', '589', '1497', 'j', 'm', '2397', 'a', 'd']

Ex Output:
a, d, h, i, j, m, n, p, y


Ex Input:
['7295', 'k', 'f', '5235', '5565', 'u', 'p', 'l', 'm', 'c', 'x', '8937', '8857', '8669', 'o', '659', 'n', 'v', 'l', '4475', 'p', '897', 'y', '6967', '1525', '5907', '8497', '6383', '2471', 'h']

Ex Output:

c, f, h, k, l, m, n, o, p, u, v, x, y