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.

Input: Consider 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']

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


Input: Consider Input: ['t', 'x', '1699', '8727']

Output: t, x


Input: Consider Input: ['1749', 'a', 'm', 'q', '9117', 'm', '4299', '7303', '4527', 'e', '5413', 'd', '5247', '7435']


Output: a, d, e, m, q