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: ['s', 'w', '8949', '4025']

Output: s, w


Input: Consider Input: ['f', '7573', '2067', 'n', '3671', '7969', '7889', '4893', '6501', 'l', 'y', '4331', 'a', 'e', '2081', '3863', 't', 'j', '7921', 's', '7203', '7797', 'f', '4279', '1299', '987', '5003', '9071', '9559', '6061', '1889', '2653', 'm', 'w', '665', '7343', '9763', 'r', '6343', '9393', '9289']

Output: a, e, f, j, l, m, n, r, s, t, w, y


Input: Consider Input: ['8239', '7713', '8879', '6845', '1301', 'o', 'e', '6865', 'o', '9299', '6173', 'f', '8995', '6519', 'w', 'f', '5989', 'a', '2297', 'o', 'q', 'v', '6233', 'f', 'm', 'x', 'n', '4399', '8513']


Output: a, e, f, m, n, o, q, v, w, x