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: ['491', '229', 'g', '6677', '4793', 'h', 'x', 'a', '2333', 'u', 'l', '785', 'p', '7331', '653', '5193', '5415', '8417', 'v']

Output: a, g, h, l, p, u, v, x


Input: Consider Input: ['v', '2989', 'z', '7843', 'e', '9923', 'y', 'b', '7611', 'u', 'u', '6227', '3145', 'w', '6451', 'g', '3129', 'o', 'r', 'z', '8349', 'u', 'h', 'd', 'g', 'a']

Output: a, b, d, e, g, h, o, r, u, v, w, y, z


Input: Consider Input: ['m', 'q', '5083', '1389', '2813', 'k', 'c', '1009', '2205', 'w', 'q', '177', 'g', '7001']


Output: c, g, k, m, q, w