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: ['p', '5229', '7521', 'y', 'n', 'u', 'c', '4047', '781', 'a', '4707', '7149', 'j', 'm', 't', '515', '7691', 'h', '4879', 'j', '6593', 'n', 'p', '2949', '1343', 'y', '2629', 'p', 'b', 'b', '2861', 'a']

Output: a, b, c, h, j, m, n, p, t, u, y


Input: Consider Input: ['g', '7517', '3173', 'd', '2143', 'n', '8507', 'l', '8369', '225', 'e', 'l', '9511', 'p', '1317', '5651', 'p', '1125', 't', '739', '6453', 'l', 'g', '8555', '8075', 'x', 's', 'd']

Output: d, e, g, l, n, p, s, t, x


Input: Consider Input: ['6189', '6263', 'd', 'o', 'f', 'g', '5199', 'u', 'e', 'y', 'z', '7291', '4341', 'x', '9089', '5725', 'q', 'v', '9525', '3933', '3989', '5979', '2185', '2245', '1529', 'd', '7009', 'w', 'b', '4551', '5973', '595', '4089', 'f', '3325', '8627', 'p', '2997', 'u', '1973', '447', '6899', '8019']


Output: b, d, e, f, g, o, p, q, u, v, w, x, y, z