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:
['6599', 'f', 'c', '661', 'q', 'e', '1951', 'f', 'f', 'a', 'd', '9521', '853', 'n', 'w', '6451', '5549', 'k', 't', 'l', 'z', 'm', 'k', '567']

Ex Output:
a, c, d, e, f, k, l, m, n, q, t, w, z


Ex Input:
['a', '2579', 'f', '6787', '123', '225', '6499', '4419', 'o', '1785', '7981', 'z', 'b', '2441', '2821', 'o', 'k', '2747', 's', 'u', 'q', '3901', '7629', 'k', 'm', 'q', '6577']

Ex Output:
a, b, f, k, m, o, q, s, u, z


Ex Input:
['3349', '4871', '1305', '3453', 'p', '1593', 'j', 'y', '7939', '9097', 'u', 'i', 'f', 'p', 'd', 'l', 'u', '1889', 'l', 'n', '7553', '927', 'n']

Ex Output:

d, f, i, j, l, n, p, u, y


