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: ['7073', 'd', 'e']

Output: d, e


Input: Consider Input: ['7013', '8755', 'u', '9377', 'n', '6997', '507', '8557', '9745', 'g', '3019', '93', 'l', '1219', 'a', '393', '2573', 'q', 'b', '6101', 'e']

Output: a, b, e, g, l, n, q, u


Input: Consider Input: ['8071', 'd', 't', '4261', 'o', 'd', '9813', 'k', '4939', '9879', 'd', 'k', 'e', 'v', '8903', 'n', '5039', '1339', '629', '2651', 'u', 'b', 'k']


Output: b, d, e, k, n, o, t, u, v