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:
['8281', '4831', '1329', 'g', 'e', '8879', 'n', 's', 'x', 'j', '6305', 'j', '921', '3677', '5107', 'n', 'j', '9285', 'a', '5329', '6671', 'c', '9283', 'l', 'a', '7907', 'q', '7605', '855', '6477']

Ex Output:
a, c, e, g, j, l, n, q, s, x


Ex Input:
['8319', 'f', 'w', 'w', 'v', '6521', '4503', 'b', 's', 'b', '9651', 'k', '4635', '2195', '7537', '6839', 'i', 'd', 'b', '205', 'q', '7333', 'q', '5129', '4921', 's']

Ex Output:
b, d, f, i, k, q, s, v, w


Ex Input:
['x', 's', '6813', '6083', '8959', 'n', 'e', 't', 'l', 'x', 'o', 'd', '2709', 's', 'm', 'v', 'm', '9365', '1229', '5891', 'n', '713', 'e', '6709', '1755', '1733', '3843', '4275', 'l', '6761', 'w', '8111', '9291']

Ex Output:

d, e, l, m, n, o, s, t, v, w, x