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: ['n', '7337', '6887', '2203', '4663', '2837', '6451', '959', '8027', 'p', 'v', 'q', 'g', '8059', '6151', 'v', '7097', '6583', '7637', '2367', 'w', '9603', '5365', '3773', '1707', 'k', 'x', 's', 'c', 'u', '3641', '6137', '1207', 'k', '5531', '4543']

Output: c, g, k, n, p, q, s, u, v, w, x


Input: Consider Input: ['1979', 'b', 't', '1101', '7953', '2451', '7539', '6833', 'u', '49']

Output: b, t, u


Input: Consider Input: ['9747', 'x', '2405', '6273', '2855', '8805', 'j', 'y', 'a', '5969', 'm', '3083', 'a', 'b', 'm', 'c', 'u', 'b', 'q', '5801', '4201', 'j', 'x', 'z', 'k', '8427', 'j', 'e', '1031', 'y', '495', '1447', 'd', 'r', 'h', 'b', 'x', '4275', 'r']


Output: a, b, c, d, e, h, j, k, m, q, r, u, x, y, z