Definition: 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: ['v', 'c', 'w', '4439', 'j', 'a', '1013', '7469', '4861', '5453', 'c', 'y', '1027', '3347', '489', '9575', '6495', 'd', 'n', 'r', '6349', 'r', 'a', '8761', '5051', 'z', '9175', '4915', 'a', '4111', 'u', 't', '1437', 'x', 'k', '2237', '2619', '6801', 'f', 'j', '5527', '405']
Output:
a, c, d, f, j, k, n, r, t, u, v, w, x, y, z