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: ['w', '8777', 'y', 'e', '8015', 't', 'w', '53', '9149', 'e', 'k', '1837', 'b', 's', '4007', '4905']

Output: b, e, k, s, t, w, y


Input: Consider Input: ['5337', '4877', '9443', '3445', 'u', '2571', 't', 'n', 'x', '1985', '5145', '3397', 'p', '9259', 's', 'x', 'u', 'c', 'g', 't', 'j', '829', '8273', 'e', 'j', 'r', 'x', '865', '4773', 'h', '4407', '8591']

Output: c, e, g, h, j, n, p, r, s, t, u, x


Input: Consider Input: ['t', 'x', 'i', '9261', '859', '4019', 'b', 'b']


Output: b, i, t, x