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:
['e', '8391', '7065', '6141', '3335', 't', 'i', 'c', '1791', '6333', 'b', 'z', '1621', 'e', 'h', 'u', 'o', 'q', '3195', '6507', '3253', 'c', '2067', '3917', '7111', 'r', 'j', 'd', '3987', '9139', 'm', '981', 'l', 'f', '2417', 'w', '9983', 'h', 'd', '6021', 'a', 'f']

Ex Output:
a, b, c, d, e, f, h, i, j, l, m, o, q, r, t, u, w, z


Ex Input:
['5553', 'f', '3881', '8867', 's', 'd', 'a', '375', '7889', '3949', '2905', 'w', 'q', 'q', 'd', '4203', 'i', '2601', 'y', 'p', 'k']

Ex Output:
a, d, f, i, k, p, q, s, w, y


Ex Input:
['989', '1515', '3425', '2137', 'g', '4707', 'd', 'j', '6927', 'k', 'm', '2495', 'f', '3547', '6833', 'z', '3249', '8833', 'c', 'x', '6033', '6845', '9137', 'v', '7345', 'y', 'p', '1167', 'n', '3997', 'k', 'b', 'a', '5115', 'v', '7751', '9433', 'f']

Ex Output:

a, b, c, d, f, g, j, k, m, n, p, v, x, y, z