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.

Example Input: ['b', 'd', '8153', 'u', '3695', '5317']
Example Output: b, d, u

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

Example Input: ['r', 's', 'm', '8939', '6357', 'g', 'x', '3251', '6801', 'c', 'k', 'a', '9413', 'v', 'p', 'c', 's', 'w', '3737', '5777', 'q', 'm', 'a', '697', '8929', '9227', '515']
Example Output:
a, c, g, k, m, p, q, r, s, v, w, x

