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', '491', 'x', 'u', 'z', 'q', '5411', '7629', '8261', '8629', '1441', '5139', 's', 'm', '6463', 'u', 'z']

Output: m, q, s, u, w, x, z


Input: Consider Input: ['459', '1729', 'b', 'c', '9619', '4461', '4347', '6733', 'i', '3631', 's', 'j', 'i', 'r', '5293', 'q', '7397', '4309', 'c', 'n', 'k', '197', 'q', '8139']

Output: b, c, i, j, k, n, q, r, s


Input: Consider Input: ['1075', '9021', '7533', 'j', 'r', '4513', 'o', '5357', 'o', '4887', 'o', 'k', 'x', 'l', '1713', 'o', 'n', '9663', '847', 's', '1869', 'j', 'l', '5463', 'a', 'v', 'p', 'l', 'w', 'p', 'o', '3461', '6337']


Output: a, j, k, l, n, o, p, r, s, v, w, x