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: ['g', 'p', '2925', 'n', 'o', 'y', '6381', 'l', '4963', 'g', 'm', 'u', 't', '9389', '3787', '7713', '1251', '779', 'i', 'w', '9869', 'y', 'y', '3881', 'k', 't']

Output: g, i, k, l, m, n, o, p, t, u, w, y


Input: Consider Input: ['2247', 'w', 'h', '4675', '6153', 'f', '6029', 'o', 'd', 'j', 'z', 'y', 'i', '6899', '3917', 'u', '6447', '6405', 'a', '1705', '8585', 'v', 'f', 'r']

Output: a, d, f, h, i, j, o, r, u, v, w, y, z


Input: Consider Input: ['6989', '8795', 'm', '4011', '653', '787', '3201', 'q', 'w', 'k', '4513', '5313', '4693', '5441', 'r', '2837', '3287', '7153', 'l', '4901', 'q', 'o']


Output: k, l, m, o, q, r, w