Given the task definition, example input & output, solve the new input case.
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: ['8129', 'a', '4245', 'y', 'm', 'a']
Output: a, m, y
Here, the unique alphabets in the list are 'a', 'y', and 'm', hence their sorted order is 'a, m, y'.

New input case for you: ['7461', 'n', 't', 'k', '4025', '2507', 'i', 'c', '4649', '4949', '9435', 'n', '5257', 'e', '7141', 'l', 'n', 't', '1493', 'k', '4697', '3509', '143', 'c', 'n', 'g', '6917', '6591', 'b', 'k', 'f', '5323']
Output:
b, c, e, f, g, i, k, l, n, t