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:
['7595', '5303', '3985', 'n', 'w', 's', 'r', 'f', '8237', 'q', 'y', 'f', '3121', '2463', '4597', 'q', '6801', 'f', 'i', '8563', '3267', 'k', '6157', 'f']

Ex Output:
f, i, k, n, q, r, s, w, y


Ex Input:
['2995', '8179', '8131', '5655', 'j', 'q', 'l', '3193', '1823', 'y', 'n', '7645', 's', '5665', 'r']

Ex Output:
j, l, n, q, r, s, y


Ex Input:
['b', '923', '5149', 'w', 'q', '3125', 'h', 'a', '6187', 'm', '3189', '961', 'f', '1999', 'g', '6253', 'd', 'a', 'u', '9365', '3139', 'b', '8855', 'g', '9449', 'a', 'z', '7199', '5035', 'e', '3569', '7321', 'o', '5157', 'n', '8497', 'w', '4451', 'g', '7073', '8611', 'o', 'c', 'p']

Ex Output:

a, b, c, d, e, f, g, h, m, n, o, p, q, u, w, z